Author Archives: Alana

Can I Install External Wall Insulation on a Cavity Wall?

At EWI Store, we receive many enquiries from homeowners who are very interested in installing EWI. However, there is often confusion as to whether it is possible to install EWI on a home with existing cavity wall insulation. In today’s post, we’re going to be tackling this question to see if we can clear things up!

What is Cavity Wall Insulation?

If your home was built after the 1920s, it’s likely that it will have been built with a cavity between the two exterior walls.

The main purpose of this cavity was to prevent damp crossing over from the outside through to the interior walls, but it wasn’t until later that people realised it could be used for another purpose. Nowadays, cavity walls are often retrofitted with an insulation material in order to increase energy efficiency and reduce the amount of heat lost through the walls.

In today’s housing stock, cavity wall insulation (CWI) seems to be the default method of wall insulation however, this isn’t to say that there haven’t been people with negative experiences of it. Damp and condensation have often been reported as a side effect of CWI, usually occurring as a result of cold bridges caused by poor installation. There are therefore many people who are quite rightly wary of CWI, so they instead look elsewhere for their wall insulation solutions.

What is External Wall Insulation?

If your home was built before the 1920s, then it’s likely to be a solid wall property. These properties present a bit of a challenge in terms of increasing energy efficiency because there is no cavity to fill, so homeowners either have to opt for no insulation (and high energy bills), internal wall insulation (IWI) or external wall insulation (EWI).

EWI provides the best solution for this type of building, as it is fitted onto the outside walls by securing the insulation boards with adhesive and fixings. A protective render is then applied to the insulation boards to create a weatherproof seal.

Unlike IWI where the thickness of the insulation is severely limited by how much floor space you can give up, EWI allows users to install insulation as thick as 200mm onto the outside walls of their properties.

Further to this, the effectiveness of CWI is dictated by the amount of insulation that can actually fit within the cavity – some cavities are just 50mm wide, so the benefits of insulating this are pretty slim.

EWI, therefore, offers increased potential for homes to massively up their efficiency. Unfortunately, it’s commonly assumed that homes with cavity wall insulation are: a) insulated well enough, and b) cannot have EWI as well as CWI.

To see what materials you will need and how much EWI may cost, visit our Materials Calculator Tool.

Can I have both EWI and CWI?

In fact, if you have CWI, then EWI is likely to reduce any problems with damp caused by the cavity wall insulation. This is because EWI completely envelopes your home in a weather-proof blanket, preventing water from entering through the exterior walls and keeping the temperature of the walls nice and warm. Because EWI wraps around the entirety of the exterior walls, there are no gaps and therefore thermal bridging is kept to a minimum.

So, because the internal temperature of the walls increases, the chances of damp and interstitial condensation are reduced. If there were any cold spots within the cavity wall insulation before, then the EWI will counteract the effect of these by maintaining a warm wall temperature.

If you currently live in a cavity insulated house and you want to upgrade the wall insulation even further, get in touch! We can talk you through the process and offer you our technical expertise.


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    Is External Wall Insulation Soundproofing?

    Noise pollution can be incredibly frustrating. Whether it’s from road traffic, railway networks, aircraft or just plain old noisy neighbours, measures can be taken to increase the soundproofing capabilities of your home.

    External wall insulation (EWI) is excellent for soundproofing. Not only does EWI improve the thermal performance of your property, but certain types of insulation can also dramatically improve the acoustics of a building. We’re going to be talking a bit about the negative impact of noise pollution on human health, and which external wall insulation system is best for preventing this.

    What are the effects of noise pollution?

    Noise pollution has proven to significantly affect children, adults and the elderly. According to research carried out by Rockwool, noise pollution can cause stress and fatigue due to disturbed sleep patterns. In turn, this can lead to health problems and a slower rate of development for children.

    The Best Insulation for Soundproofing

    If you live in a solid wall property, it’s unlikely that your home will be adequately soundproofed. This is because, generally, homes are built with insulation in the walls (cavity wall insulation) that absorbs the sound and protects the house against noise pollution. EWI is a great choice if you live in a solid wall property, or even if your property just needs an extra soundproofing boost.

    Mineral Wool insulation is the best one to go for if soundproofing is a concern. Renowned for having excellent insulating capabilities, the insulation not only reduces the amount of noise entering your home but is also all the more effective due to the fact that it is installed externally. The entire insulation system seamlessly envelopes the house and is, therefore, a highly effective solution against sound pollution. We recommend using the Mineral Wool insulation at a thickness greater than 200mm.

    Of course, with a Mineral Wool external wall insulation system, it’s not just the soundproofing capabilities that you reap the rewards of. Mineral Wool has excellent thermal insulating capabilities, is class A1 fire rated (the highest standard!) and is also very breathable. So, overall, this is a very healthy insulation material for buildings!

    How is the insulation installed?

    If you are new to the idea of EWI, it’s very simple!

    • The Mineral Wool is doubly secured to the external wall using both our Premium Basecoat adhesive and metal pin mechanical fixings.
    • Once the boards are secured to the wall, the Premium Basecoat is again applied on top and fibreglass mesh is embedded within the basecoat for extra crack resistance and tensile strength.
    • Once the basecoat is dry, a render primer is painted on and left to dry.
    • After this, a thin coat render is applied on top of the basecoat to create a decorative finish.
    • The overall result is a higher performance building in many respects, and an aesthetically pleasing, brand new finish!

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      The Lloyds Bank British Business Excellence Awards

      We did it! EWI Store has been shortlisted as a finalist in The Lloyds Bank British Business Excellence Awards in the category Small-To-Medium-Sized Business of the Year. This award celebrates resilience and innovation within some of the UK’s best businesses and we are so proud to have been shortlisted for this prestigious award!

      What is The Lloyds Bank British Business Excellence Awards?

      Attracting a variety of organisations, from small startups to large corporations, the Lloyds Bank British Business Excellence Awards is the largest and most comprehensive business awards programme in the UK. These awards acknowledge businesses that find new ways to support their communities and where employees thrive in times of hardship. This prestigious award is only awarded to businesses that are able to demonstrate clear processes aimed at supporting their local communities.

      What Have We Achieved This Year?

      Many have struggled over the past year and, to further support our community of homeowners, installers and architects, we have invested heavily in our training. This training is aimed at both new and experienced installers who are looking to either gain the necessary skills for the industry or to maintain their professional development and keep up to date with the latest processes and techniques. This year, we created an educational CPD (Continual Professional Development) programme aimed at architects which we have successfully had approved by the Royal Institute of British Architects (RIBA). This shows that our CPD course is of high quality and meets the very stringent criteria that are required to gain RIBA approval.

      Here at EWI Store, we handpick only the highest quality products to sell in our stores. We stock the full range of products from EWI Pro who are well known for their supreme range of silicone renders. Their Premium Bio Silicone Render is an award-winning render, resistant to cracking, biological growth and discolouration and thereby providing a stand-out finish for years to come. By selecting only the best products, we ensure long-lasting and high-quality results for our community.

      As usual, we would like to thank all our customers for their continued support. Make sure to keep your eyes peeled for future announcements!

      Is External Wall Insulation Expensive?

      Many of us here in the UK are interested in the idea of External Wall Insulation, with a vast range of benefits both environmental and financial it is easy to understand why. The biggest reservation many people have is regarding the upfront cost of the External Wall Insulation installation process. In today’s blog, I will explain the costs and hopefully put your financial worries to rest!


      The process of External Wall Insulation has many components; the price accounts for the required insulation materials and labour costs. The cost of EWI materials will depend on the size of the project but also what EWI materials you choose. Not only do the prices of materials vary, but some materials require fixings and some require adhesive which will also need to be accounted for within the price. This means that the cost of your EWI system will depend entirely on the specific needs of your project.


      Calculating the cost of the External Wall Insulation Materials

      As explained above, there are a lot of components to consider when calculating the price. Luckily, we have a great solution for you; not only do we have a fantastic team on hand who can provide you with a quote, but we also have an easy-to-use EWI Materials Calculator tool that takes all of the faffs out of the calculation process. If you would rather have a helping hand and some guidance, just give us a call on 02033974067.


      What is the EWI Materials Calculator?

      The EWI Materials Calculator is an online tool that enables homeowners, installers and architects to quickly and accurately calculate the correct EWI materials needed to meet their requirements for their next project. The calculator will ask a series of questions to gather how much the system will cost depending on your needs.

      Average External Wall Insulation costs:

      EWI Typical Cost
      Mid-terrace house £4,000 – £6,000
      Semi-detached house £8,000 – £10,000
      Detached house £12,000 – £14,000 +


      This may seem like a scary amount for some but if your property has solid walls, you could save between £115 and £360 a year by installing External Wall Insulation. This means, over time, the External Wall Insulation will start to pay for itself. You have to remember that not only will you save on your heating costs, but you will also reduce the amount of CO2 emissions your property emits into the atmosphere which will help the environment. Your External Wall Insulation job will also be finished with your choice of render and colour, providing additional value if your brickwork is damaged, worn down and in need of a makeover.

      If this still sounds like too much for you, there is government-backed support that you could be eligible for. Currently, there is a subsidy called the Energy Company Obligation (ECO) which was launched in December of 2018. The scheme runs until the 31st March 2022 and focuses on customers with low incomes and considered to be in vulnerable situations e.g. living in fuel poverty. Under ECO, grants are available to cover all or part of the cost of energy efficiency measures. Ask your energy provider for more information on this scheme.

      Trade Installers get fantastic prices and warranties on the system

      As an installer, you may well be eligible for our trade discount prices too; so, not only will you get a BBA-approved external wall insulation system delivered directly to the site, but also the materials you need at a great price. As a trade partner, we are also able to offer system warranties provided the installers have been on our free training course. Be sure to sign up to our Trade Account for free to receive your discounts!

      So, there you have it – if you need some help calculating the material requirements for an EWI job, give us a call or use our EWI Materials Calculator today!


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        How to Apply OCR

        How to Apply One Coat Render

        There is a wide variety of one coat renders available on the market, often chosen by homeowners due to the fact that it is a cost-effective solution while being considerably better than sand and cement render.

        We’ve recently started stocking EWI Pro’s EWI-265 OCR, which is a one-coat, cement-lime render, ideal for application using a spray machine. The product is a great solution for creating a smooth surface prior to applying masonry paint, so have a read about how to apply it!

        OCR Installation Guide: Substrate Preparation

        If the original substrate does not have a good key, we recommend using the EWI-310 Universal Primer, which contains quartz aggregate to provide a rough surface for the render to adhere to.

        Once the substrate has been primed, it may need levelling. If it’s particularly uneven, we recommend the use of the EWI-269 Lightweight Basecoat, which can be applied up to 25mm thick in one pass. The product should be mixed with 5 litres of water per 25kg of dry mix. Once combined, the basecoat should be applied at the required thickness to level off the wall. We recommend embedding a layer of Fibreglass Mesh into the basecoat to ensure its stability. Leave to dry completely before applying any further materials.

        Applying OCR

        If the substrate doesn’t need levelling, you can apply OCR straight off. The bag needs to be mixed with 5.5 litres of water, and it should then be applied at a thickness of 5-15mm (usually this is dependent upon how even your substrate is). If you didn’t apply a levelling layer to begin with, you should embed mesh into the OCR instead.

        Choosing your Decorative Finish

        OCR is not through-coloured, so a decorative finish will need to be applied on top. Many people opt for a painted finish to achieve a smooth surface texture; we recommend the use of our EWI-005 Silicone Paint, which is a highly hydrophobic masonry paint. This particular paint repels water and is very breathable, so it’s a great choice for ensuring that the render is totally sealed in.

        Silicone Paint can be tinted to create any colour, and we can even match to NCS and RAL colours.

        Interested in OCR or have any questions? Our experienced Sales Team will be happy to assist with any enquiries you may have! Find our contact details here.





        If you’re looking for an approved installer to carry out the work for you, fill out the form below and we will be in touch. We upload blog posts every Tuesday and Thursday, so keep up to date with our blog and social channels to find out more!

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          render in hot weather

          Top Tips for Rendering in Hot Weather

          So, we are in a heatwave! We all know how that affects us; you feel sluggish and can barely bend down without breaking a sweat, your throat feels dry no matter how much you drink and the mere act of existing becomes exhausting. But, how does the heat affect the rendering process?

          In this blog, I am going to go over the issues with rendering in hot weather, and our top tips to overcome them. To all those rendering out there in this blistering heat, I salute you!



          We sometimes receive complaints from homeowners regarding how their render has dried; the most common complaint is the appearance of pinholes caused by the render drying too fast. Normally, the cause of this is due to applying render in too hot weather conditions or in direct sunlight.

          All renders have specific temperature margins and, when not applied within these margins, the product will not perform at its best. These temperature margins tend to be around 5˚C – 25˚C but, with all the different render options out there, the margins will vary from product to product. It is good practice to always check your product packaging to determine its specific temperature requirements.


          pinholes in silicone render


          Switching to a different render product is not a good solution to this problem because pinholes affect most types of render. On top of this, you will lose all of the product-specific benefits, for example, a silicone render is extremely flexible, breathable and hydrophobic, unlike many other renders.

          There are no long-term side effects or damage to your property that can occur with pinholes; the problem is purely visual. If you can avoid pinholes by following the advice of this blog, you will notice all the wonderful advantages to rendering your property. Check out our blog The Benefits of Using Silicone Render to learn more.

          Renders are bound to dry at accelerated rates in extreme heat, therefore increasing the likelihood of pinholes. However, hope is not all lost as we have a method to prevent this.

          Using a render primer reduces the chances of pinholes occurring. This is because basecoat is very dry and porous and will absorb moisture from the render very quickly. Render primer, however, prevents this from happening by creating a barrier between the basecoat and render. We recommend applying two coats of render primer; this increases the strength of this barrier, further preventing the basecoat from absorbing moisture from the render.

          Uneven texture

          It can take four people over three hours to apply render on a 200 square meter surface. If you don’t have enough time to apply the render, you may rush the application and not be able to use the correct technique; this may result in an uneven textured finish, which can create the illusion of discolouration. The correct way to apply the render is in circular motions, not in strips; this will help you create that smooth and uniform texture that you desire.


          Silicone Render Uneven Texture


          If you must complete your project in the peak of summer, the key is to get up as early as possible and get going! We have seen many installers start the process as early as 5 am – it may be hard to drag yourself out of bed, but it will definitely be worth it in the long run. Where possible, avoid applying render in the middle of the day as this is when the sun is at its hottest. Many of our installers work by avoiding the sun and following the shadows. This means they will only apply the render on the shadowed areas; as the angle of the sun changes, these shadows will move and so should you! This means you can keep applying your render whilst out of direct sunlight.

          The best solution to both aforementioned issues is, of course, to apply the render within the correct temperature margins.

          Tips for Your Health

          Remember what I said earlier about a dry throat? In this heat, it is crucial to stay hydrated. Without sufficient hydration, you are putting yourself at risk of lethargy and headaches. Lack of hydration, especially in such labour intensive work, could even cause you to pass out! Consider bringing a fridge on-site for the duration of the project and make sure to keep it fully stocked with water.

          Avoid caffeine because this can be extremely dehydrating. If you really need your morning coffee boost, ensure you are drinking enough water to compensate.

          Keep your clothes on! We know how tempting it can be to take your shirt off, especially when you can feel yourself cooking and getting all stuck to your sweaty clothes however, this is not a wise move. By removing your shirt, you are leaving yourself open to sunburn. We instead recommend wearing light coloured cotton shirts because this will keep you cool whilst keeping the sun off your back. If you really can’t resist then make sure you are regularly applying suncream.

          Working in such hot conditions can have more serious consequences if you don’t take the correct precautions. Make sure to keep out of the sun whenever possible, and take regular breaks in the shade. If you are not careful, you could end up with heatstroke which can cause permanent damage to your vital organs.

          Top Tip Summary:

          1. Use a render primer
          2. Follow the shadows
          3. Stay hydrated
          4. Stay away from caffeine
          5. Keep your shirt on
          6. Keep out of the sun


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            Is External Wall Insulation Safe

            Is External Wall Insulation Safe?

            Customers often call us to ask whether external wall insulation is safe to install on their homes. EWI Pro systems are BBA-approved, which means that they have been rigorously tested by the British Board of Agrément, who have deemed that they are safe and suitable for installation onto UK homes.

            In today’s blog post, we will discuss how our external wall insulation systems have been designed to ensure the highest level of safety. 

            Securing External Insulation Boards – Dual Fixing

            The EWI Pro system is designed so that the external wall insulation boards are fixed to the substrate using the dual-fixing method of both adhesive and mechanical fixings. This ‘belt and braces’ design ensures the stability of the system so that in the unlikely event that the adhesive fails, the fixings are still there to hold the boards up. 

            The EWI Pro system also consists of two adhesives of different strengths. For example, our Premium Basecoat (EWI-225) is our strongest adhesive and is always used with Mineral Wool insulation boards that are much heavier. Alternatively, the EPS Basecoat (EWI-220) is ideal for use with lightweight foam insulation boards such as EPS and XPS. Ensuring that the adhesive is of the correct strength for the weight of the insulation board is essential for a safe and secure system. 

            Fire Safety of External Wall Insulation Materials

            How fire safe your system is will greatly depend upon the type of insulation that you choose. 

            Rockwool Mineral Wool boards are rated as Euroclass A1 non-combustible and are the safest insulation material you can have installed on your property. The Rockwool insulation boards work to contain the fire and prevent it from spreading throughout the building. As well as this, they don’t release toxic emissions or smoke when exposed to fire.

            The EPS system has been designed in such a way so that in the event of a fire the EPS would simply melt within its cement-based plaster enclosure. The mechanical fixings would support and hold the structure in place, so although the system wouldn’t withstand the fire, it wouldn’t contribute towards the spread of it.

            Fibreglass Mesh for Reinforcement

            We often talk about the use of reinforcement mesh in the context of ensuring that the render topcoat doesn’t crack. However, Fibreglass Mesh plays an important role within the external wall insulation system, enhancing its tensile strength to keep the boards securely tied to the wall.

            Fibreglass Mesh strips are embedded within the basecoat layer and are overlapped by 10cm across each edge. This creates an added layer of reinforcement that spans across the entire surface area of the system.



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              How to calculate the cost of an External Wall Insulation system

              Calculating the cost of an external wall insulation (EWI) system is not as simple a task as you might think; the price not only accounts for the insulation materials but also the installation of the system, labour costs, square meterage (for example, our reinforcement mesh comes in 50m rolls while a bag of EWI-220 Adhesive will cover 3m2 of the wall), the choice of decorative finish and so on. What’s more, not only do the prices of materials vary, but some materials require fixings and some adhesive which will also be included in the price. Therefore, the cost of your EWI system depends entirely on the needs of your project. So, how does one go about calculating the cost of their EWI system?

              Calculating the cost of the External Wall Insulation Materials

              At EWI Store, we have just the solution for you. Not only do we have an excellent team on hand who will be happy to provide a quote – simply give them a call with some rough measurements of the area that needs to be insulated, and they can quickly calculate the EWI materials you need using their expertise – but we also have a fantastic tool available at your fingertips…

              The EWI Materials Calculator

              Whether you have experience with external wall insulation, or you’re keen to have a go, you can use our accurate, easy-to-use EWI materials calculator!

              What is the EWI Materials Calculator?

              The EWI Materials Calculator is an online tool that enables homeowners, installers and architects to quickly and accurately calculate the correct EWI materials needed to meet their requirements for their next project. The calculator will ask a series of questions to gather how much the system will cost depending on your needs.

              The questions the EWI Materials Calculator will ask are as follows:

              The information you need for the EWI Materials Calculator

              You can choose between three options depending on what you are interested in: eco, premium and standard. This relates to the decorative finish you want on your walls.

              •  Amount of metres squared needed

              To calculate the number of metres squared needed, multiply the width by the height of each wall you are going to insulate. Do not subtract windows or doors; this will give you an incorrect result as our calculator considers wastage in the final calculation.



              So, whether you are a homeowner looking to install external wall insulation or apply a fresh new render façade to your home, a solid wall insulation installer looking for an easy-to-install product (at a great price) or an architect looking for a way to vastly improve the thermal efficiency of an old property, you have come to the right place.

              Trade installers get fantastic prices and warranties on the system

              As an installer, you may well be eligible for our trade discount prices too; so, not only will you get a BBA-approved external wall insulation system delivered directly to the site, but also the materials you need at a great price. As a trade partner, we are also able to offer system warranties provided the installers have been on our free training course. Be sure to sign up to our Trade Account for free to receive your discounts!

              So, there you have it – if you need some help calculating the material requirements for an EWI job, give us a call or use our EWI Materials Calculator today!

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                Applying Render to OSB

                How one should go about applying render to OSB is a question that we get asked on a near-daily basis. The simple answer is that applying render directly onto the OSB is not an ideal situation – it’s important to remember that at the end of the day, OSB is wood.

                Nevertheless, there is a solution for rendering OSB, and we’re going to talk you through the best way you can do this!

                Rendering OSB: Render Carrier Board

                When rendering any substrate, especially when rendering OSB, consideration needs to be taken as to the suitability of the substrate for the materials that you are using. OSB is not completely waterproof and will inevitably absorb water from the basecoat, which can cause the wood to warp, eventually hindering structural integrity.

                To avoid this, the best solution is to use a render carrier board. However, the render carrier board needs to be attached to battens, rather than to the OSB directly. This is because the two separate fabrics (the RCB board and the OSB) need ventilation between them to allow moisture to escape, and to avoid a situation where water builds up between the two materials. An air gap between the two is therefore necessary for the reduction of condensation.

                The best course of action is to:

                • First, staple a breather membrane onto the OSB substrate – this will help prevent the build-up of condensation on the surface of the wood.
                • Next, install timber battens on top of the OSB (the positioning of the battens will depend upon the size of the render carrier board you are using).
                • Once these are in place, you can secure the render carrier boards onto the battens with wood screws.

                The spacing of the boards will depend on the type of render carrier board you are using, but generally, you would leave 4-5mm between each board.

                After the boards are in place, the gaps between them need to be covered over by a render carrier board tape. We recommend a tape that is breathable with a self-adhesive membrane, so it will prevent water vapour from gathering in the gaps between boards.

                Basecoating the Render Carrier Boards

                Render carrier boards don’t require priming because they are specially designed for being rendered, so you can go straight into applying the basecoat with no problems.

                Although it is possible to use the 220 Basecoat Adhesive, we recommend using the 225 Premium Basecoat as a basecoat for extra strength and breathability. At this stage, the necessary beading required for the structure is sunk into the basecoat along with fibreglass mesh – remember to overlap each strip of fibreglass mesh by about 10-15cm.

                Allow the basecoat to set for a period of 24-48 hours, before priming the basecoat with a Render Primer. The type of primer you use will depend upon the type of render, for example, if you were to render using Silicone Render (we recommend this one for buildings that require a high level of breathability), you would need to use our SiSi Render Primer. This can be painted on and then left to dry for 12 hours.

                Rendering the Basecoat Layer

                After all that essential preparation of the OSB and RCB boards, you are finally ready to render. Using our ready-to-use Silicone Render, apply it onto the substrate using a trowel. The render should go on at a thickness that matches the chosen grain size – for example, if you’ve chosen a 1.5mm grain size finish, then you should apply the render at 1.5mm thick.

                Once distributed across the surface, rub up the surface of the render with a plastic render float to bring out the texture and achieve a consistent finish, then leave to dry for 24-48 hours. 

                Struggling to chose a Silicone Render colour from our selection? Order a colour sample here.


                Want to learn more? Come to one of the EWI Pro training centres!  More information found in the video below.


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                  Can I install EWI onto my flat?

                  There seems to be a bit of a gap in information out there about whether it is possible to install external wall insulation (EWI) onto a flat, so we wanted to answer this question for you and provide as much information as possible for any flat-owners who are considering EWI!

                  In most cases the answer is yes, you can install EWI onto a flat. However, usually the insulated render system is sealed at the top where it meets the soffit of the roof. So, on a groundfloor flat the insulation must be sealed at the top by other methods. This is because if it isn’t sealed, the exposed edges of the insulation can allow for water to seep behind the back of the insulation boards which can in turn effect the integrity of the EWI system, and water can then also enter the property through the walls causing problems with damp and mould.

                  We would recommend that EWI is most ideal for people who own a ground floor flat. This way, the EWI is at least sealed at the base so to prevent too much heat loss and water ingress, and the EWI will most likely be less noticeable.

                  So how do you install external wall insulation onto a flat?

                  Installing external wall insulation onto a flat is a slightly different process than with a normal house. This is because if the top of the insulation is exposed, i.e. does not meet the soffit of the roof, then certain actions will have to be taken to ensure that the EWI on your flat is water-tight.

                  There are a few options to consider in order to achieve a water-tight finish:

                  With the upper ledge of your insulated render system exposed, you will always need to use a verge trim to protect the EWI from water exposure. One option is using a basic verge trim which screws into the wall above the EWI. However, this is not entirely water tight because the top of the verge trim is not sealed, so you will need to use a sealant along the upper edge of the external insulation to prevent water running down its back.

                  The second option is using a Grind-in verge trim. As the name suggests, this is a verge trim with the length of its upper edge inserted into the wall surface. However, you have to first damage the surface of the existing wall to insert the verge trim, and the result is that it’s still not completely watertight. This method is therefore still a bit risky.

                  We suggest that the best option is to use lead flashing with a normal verge trim. This doubles up the waterproofing so that the lead flashing protects the verge trim, and the verge trim protects the top of the EWI.

                  As for the base of the external solid wall insulation, if it’s exposed (because your flat is not on the ground floor), then we recommend the use of white PVC so that it will look nicer for your neighbours below to look up at.

                  Pro’s of installing external wall insulation onto your flat

                  EWI is a great way to save energy on your heating bills. Most flats have electric heating, which is far more expensive than gas heating. This means that heat loss through the external walls of a flat is much more problematic for you as the homeowner, because you then need to spend even more money on re-heating the flat. EWI can dramatically reduce the amount of heat being transferred through the walls of your flat and save you a lot of money on energy bills every year.

                  As well as this, people who live in flats are often in a more built-up area which suggests more noise from road traffic. For people living on ground-floor flats this is potentially more of an issue and can be exceedingly unpleasant, so installing insulated render can greatly improve the amount of noise that enters your home.

                  People living in flats are also the most likely candidates to be struggling for space. EWI takes up absolutely none of the internal floor space, which means that your property will not lose any value due to a decrease in the size of its rooms and you will still have plenty of moving around space!

                  Cons of installing EWI onto your flat

                  If you install external wall insulation onto your flat, depending upon the thickness of the insulation boards, it could mean that the external walls of your flat will physically stand out from the rest of the building and the necessary verge trim may not be a particularly attractive feature to look at. Also, depending upon the external walls of the rest of your building, you might need to spend more to ensure that your render matches the overall look of the building. There are a number of ways you can do this, for example we offer a variety of very realistic looking brick slips which could work really well at blending the EWI on your flat in.

                  Most flats are lease-hold only, so you would likely need to ask for permission to install EWI, which is potentially a long and difficult process. It can be an expensive job for a small property and is not guaranteed to be as energy efficient as if you were to insulate an entire house, for example. Also, you will have increased scaffolding costs if your flat is on an upper level.

                  People who live flats live in very close quarters with their neighbours, so any work being done to your flat is likely to be more disruptive. Upset neighbours may therefore complain about any disruption during installation time, and may not be all too pleased with the finished look.

                  The best thing to do when considering an EWI installation is to seek professional advice. We recommend that you hire a surveyor to discuss the feasibility of installing EWI onto your flat. Our staff are all extremely knowledgeable about EWI, and are always happy to help in any way. For any enquiries, please do not hesitate to call us here at EWI Store.

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                    Is External Wall Insulation worth it in 2021?

                    2021 is here, and with it comes a lot of uncertainty and worry. For homeowners out there, it can be a difficult decision whether or not to make an investment in something like external wall insulation – while the benefits of EWI are vast, it’s not a cheap process.

                    We’ve put together a list of reasons for why external wall insulation is worth investing in, so read on if you want to be convinced…

                    Rising Energy Prices

                    Some of the biggest concerns for people are the threat of energy prices rising even higher than they already are. Energy prices go up by 5% each year, and with Brexit applying pressure to all sectors, it’s likely that we will see a change in energy prices.

                    In these circumstances, you can either vow to switch off everything and cope with it, or you can be ahead of the game. Invest in an energy-saving measure such as external wall insulation, and you can ensure that any future money spent on heating was well-spent rather than wasted.

                    Housing Crisis

                    In 2019, new-build properties where being vastly criticised for their apparent low-quality. There are definitely pros and cons of investing in new-builds, however, their resale values tend to be static for the first five years. Investing in older properties that require a little bit more TLC is the preferable choice for many buyers; external wall insulation is a great way to boost the efficiency and subsequent value of the property, bringing it in line with new-build standards while also giving it a bit of a facelift

                    Climate Change

                    Climate change is being talked about more and more in the media, portrayed as a looming threat that needs to be dealt with immediately. This leaves everyday people on the ground wondering what on earth they can possibly do to prevent this oncoming disaster, besides the standard solutions.


















                    External wall insulation is a good option to go for, especially for those who live in properties with very low energy efficiency. EWI will reduce your energy consumption, improve your carbon footprint and save you money on bills – it’s a no-brainer. There are even EWI systems that are environmentally friendly, such as our Wood Fibre insulation system.

                    2021 is looking to be a year of uncertainty, but we hope that this won’t stop people investing in being more environmentally conscious and energy aware. If you’re curious about external wall insulation and how exactly it’s installed, give us a call and we would be happy to have a chat with you.


                    Best Performing External Paint – EWI Pro Silicone Paint

                    What are External Paints?

                    External paints have a variety of uses. They can be used on several different surfaces including but not limited to concrete, render, pebbledash, metal, and soft wood.

                    A good exterior paint can improve your homes external appearance and protect it from temperature changes, moisture and fading. External Paint is essentially the ‘go to’ product for covering most rendered building facades. It’s decorative and protective.

                    EWI Pro Silicone Paints

                    Looking for the best performing external paint? Here at EWI Store we supply a range of EWI Pro Silicone Paints including EWI-005 Silicone Paint, EWI-007 Nano Drex Silicone Paint and EWI-006 Premium Bio Silicone Paint.

                    EWI Pro Silicone Paints are high quality and can be used both internally and externally. All EWI Pro Silicone Paints are frost-proof, vapour permeable, hydrophobic, resistant to algae growth and ideal for use with Mineral Render or as a standalone finish.

                    EWI Pro Silicone Paints are high-performance External Masonry paints. They can be painted over an existing render to refresh the facade and create a finish that appears brand new, or they can be used to paint over our Mineral Render to seal the render in.

                    Application is dependent on the weather conditions, EWI Pro Silicone Paint should ideally be applied 3-7 days after you have applied the Mineral Render to the substrate. Doing this will make sure that a strong chemical and physical bond forms between the Mineral Render and the external paint.

                    Why use a Silicone Paint externally?

                    Silicone Paint provides a highly breathable finish which makes it perfect as part of a render or EWI system. It is known that water ingress and moisture is detrimental to rendered homes and to external wall insulation.

                    If water manages to ingress into the external wall insulation system, it has the potential to reduce its thermal capabilities and can damage the system during the freezing and thawing process. Ingress of water within a render-only system is especially bad, as this water will cause damage to the render. There is a risk this moisture will seep into the walls of the property and inevitably cause damp patches on the internal walls, particularly with solid wall properties.

                    This is where Silicone Paint comes in. Silicone Paint creates a protective barrier against this issue. The breathability of the Silicone Paint allows moisture and water to escape through its surface and prevents moisture from passing through, this is because the silicone properties within the paint repels water vapour. Because of its vapour permeability, Silicone Paint also has frost-proof qualities (This means frost will not cause damage by settling on its surface or within the actual Silicone Paint itself.)

                    We always suggest sealing Mineral Render with a high-performance External Paint. Mineral Render is our fastest drying render, making it perfect for use in cold climates, however, its ingredients mean that if it’s exposed to the elements for a significant period of time it can be susceptible to lime bloom. This is why it becomes necessary to apply Silicone Paint over the surface, to prevent water from passing through and causing the formation of lime bloom on the render beneath.

                    What Colours are Available?

                    EWI Pro Silicone Paints are available in a multitude of different colours. Here at EWI Store we are able to colour match any RAL or NCS colour. This means we have a highly competitive range when compared to other external paint suppliers. We can match even the finest nuance of colour. Below are the colour options available online at

                    Colour OptionsColour OptionsColour OptionsColour options

                    If you are interested in EWI Pro Silicone Paints we have paper colour charts which we give out free of charge to help give you a visualisation of the colour, just bear in mind that these charts are not a 100% accurate representation which is why we recommend ordering a coloured sample pot before committing to that colour.

                    Choosing Your Perfect Silicone Render Colour

                    After reading about all the amazing benefits rendering your home can provide, you have come to the conclusion that Silicone Render is the render of choice, but with all the available colour options you can’t decide what to choose.

                    Fear not, you have come to the right place! In this blog I will be discussing our Silicone Render colour range here at EWI Store.

                    We have an extensive range of colours because we are able to colour match any RAL or NCS colours. This means we have a highly competitive range when compared to other render suppliers. We take colour matching seriously and can match even the finest nuance of colour.

                    Silicone Renders are an ideal choice when colour longevity is an important factor to you. Our range of Silicone Renders come pre-coloured and have self-cleaning and anti-bio growth properties which means your colour will stay clean and bright for longer. Our Silicone Renders are also UV resistant which helps prevent colour fade.

                    Is white too bright?

                    Many people choose to avoid a pure white render in fear of it appearing too bright in the summer months. Luckily, we are able to offer a range of white and off white shades including but not limited to Pure White, Platinum, Ice, Ivory and Linen.

                    To see our full online range please take a look at our Silicone Renders. Choosing an off-white shade may be what you are looking for as this will give you that clean white finish whilst not being as bright as the brightest shade.

                    If you do opt for our ‘Pure White’ shade then you can choose between grain sizes of 0.5mm-3mm. This texture may give your white a more diffused look preventing the shade reflecting too much light in the summer months.


                    Looking for something bolder?

                    Perhaps you are looking for a dark grey or a bright orange, whatever you are looking for we have got you covered!

                    Something to consider when opting for a more unusual colour choice is ensuring that this colour will complement the surrounding area, don’t worry if you make a mistake choosing a colour though, as you can always cover this up with our coloured Silicone Paint.


                    Fancy Mixing it up?

                    Maybe you do not just want one colour, maybe you want to enhance a particular part of your house. Why not choose a contrasting colour, like black against white, or if you are feeling really adventurous, blue against orange?

                    If you are still unsure on what colour to choose, try out our Colour Render Tool. This tool enables you to test out different render colours on real photos of your home. If you need a bit of help figuring out this tool, then check out our YouTube Tutorial.

                    Colour Guides

                    If you are interested in our Silicone Render, we have paper colour charts which we give out for free to help give you a visualisation of the colour, just bear in mind that these charts are not a 100% accurate representation as these have a smooth finish.

                    If you are looking for an accurate colour representation, then consider visiting us in-store to have a look at our colour sample chart or buy one online at This chart is more accurate due to the grainy texture and the fact they are made from our actual render.

                    We also offer Coloured Render Sample pots.

                    For more information consider watching our YouTube video

                    The Best Render to use in Winter

                    Rendering in winter is a challenge that all professional renderers face. Choosing the right materials that can be used in low temperatures is particularly tricky, especially when there is an expensive risk of render failure.

                    We have a range of solutions for making sure that nothing can go wrong even in the winter months, so keep reading to find out about the best renders to use in winter!

                    Using Mineral Render in Winter

                    Mineral Render is a great choice for winter installations. It’s essentially the dry-mix version of our thin coat renders; it has grains within the render and it’s applied in a very thin layer. The only thing that makes this render different is the fact that it contains portland cement, which enables it to dry a lot faster than our other thin coat renders.

                    Faster drying times in winter are essential, as temperatures drop overnight, and wet render exposed to freezing conditions leads to render failure. Mineral Render does require painting with Silicone Paint, but despite the added cost of this it’s a much more effective material to use in the winter months.

                    What sets mineral render apart from silicone renders, is the way in which it dries. Mineral render dries by a chemical reaction rather than water evaporation like silicone renders, which means it can dry quickly even in the winter months.

                    Using the Winter Adhesive

                    The Winter Adhesive is a basecoat designed for use down to temperatures of zero degrees. That means that it’s perfect for those winter months when the weather is miserable and work is continuously stalled due to low temperatures.

                    The basecoat is essentially the same as the EWI-220 EPS Basecoat Adhesive in that it can be used as an adhesive for securing EPS insulation boards to a substrate, so the plus side is that it also helps to enable the installation of EWI in cold climates.

                    Using the Render Accelerator in Winter

                    Winter installations tend to be all about drying times, and the render accelerator really helps with this issue. It’s essentially an additive that you mix into your ready-mix render before applying as normal – the accelerator speeds up the process of drying before the wet render can be affected by the weather. The render accelerator works great with our range of silicone renders. Silicone renders dry by water evaporation which means they need a helping hand during the colder months, render accelerator is the help silicone renders need, making them more usable during the winter.  

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                      We are Supporting the Poppy Appeal!

                      What is our involvement?

                      We are delighted to announce we are supporting the British Legion’s Poppy Appeal this year. With the support of EWI Pro, we are delighted to announce that we will be donating £1 for every £100 spent on EWI Pro products through EWI Store directly to the Poppy Appeal.

                      Impacts of Covid-19 on the charity

                      While COVID has impacted all of us this year, much of the fundraising carried out by the British Legion is reliant on face to face collections and with the COVID restrictions in place this has had a dramatic impact on what they have been able to do.

                      What is The Poppy Appeal?

                      The British Legion help members of the Royal Navy, British Army, Royal Air Force, veterans and their families.

                      While discussing our charity partner this year, several of our employees were vocal with regards to their support of the Poppy Appeal.

                      Shane- “I’ve joined British Legion to support our past and present veterans. It’s important to me to carry on collecting for the British Legion as they supported my family, when my grandfather was killed in
                      El-alamein on 27th of November 1941, at age 23.”

                      Matt- “I am delighted that EWI Store are supporting the Royal British Legion Poppy appeal this year as this is very close to me having personally served in the Royal Navy as a Gunner and coming from a family with many members that served within the British Armed forces.”

                      Joe- “As an ex Royal Navy Stoker I fully support adopting the RBL. I have ex shipmates who used their services after the Falkland War and their support was vital.”

                      If you would like to donate directly to the Poppy Appeal, please click here.

                      Installing Render and EWI During the Winter Months

                      Installing Render and EWI During the Winter Months

                      We typically consider the rendering season to be from the start of March to the end of November, but over the past few years, we are noticing more and more of our installers braving the British Winter and installing render systems right through the year.

                      Winter obviously tends to be cold, but we also get lots rain and sometimes even snow! All of these conditions can have a negative impact on your work and affect the products you are using. This is why it is crucial to select the appropriate products when installing during the colder Winter months.

                      Winter products at EWI Store

                      Here at EWI Store we sell a range of products to allow you to render / apply EWI during the Winter months – we look at some of these in a bit more detail below.

                      Winter Adhesive

                      Winter Adhesive is a great and versatile product –  it can be used as both a basecoat and an adhesive – similar to EWI-220. However, the advantage of Winter Adhesive (EWI-221) is that it can be used down to temperatures of zero degrees Celsius, where as the EWI-220 EPS Basecoat can only be used down to 5˚C.

                      The Winter Adhesive is ‘stickier’ to use and goes off that much quicker than the standard basecoats, making it a must for installing in the very cold.

                      EWI-221 Winter Adhesive is:

                      • Waterproof
                      • Frost-proof
                      • High Grip
                      • Contains microfibres for increased flexibility
                      • Hydrophobic

                      Render Accelerator

                      Silicone render is one of our most popular products here at the EWI Store. This is because it offers incredible performance in terms of flexibility, breathability and durability. Silicone Render can be used from +5°C to 25°C, but in the Winter months it can take 2-3 days to cure.

                      EWI-020 Render Accelerator can be used to speed up the drying time of our Silicone Renders. It is a liquid additive that gets added to the bucket of render and helps prevent costly render wash-off.

                      When installing Silicone Renders, we always recommend checking the weather forecast to ensure the days following application are dry so the Silicone Render has a chance to cure properly before any adverse weather, but the render accelerator also helps form a protective skin on the render again helping to protect it.

                      Silicone render is:

                      • Weatherproof
                      • Resistant to algae and plant growth
                      • Frost-proof
                      • Hydrophobic
                      • Vapor-permeable
                      • Nano-enhanced
                      • Self-cleaning

                      Mineral Render

                      If Silicone Render isn’t your cup of tea, don’t despair!

                      Mineral Render is also an excellent option in colder conditions. Our Silicone renders cure when the water evaporates out of them, which is why they struggle to go off in the winter as the cooler / humid conditions slow the rate of evaporation (although accelerator helps!).

                      Luckily, Mineral render cures using a chemical reaction (in the same way cement cures) and therefore dries regardless. Mineral Render can give you the same look and breathability that Silicone Render can offer, however you do have to paint it with Silicone Paint once the mineral render is installed. Please note that unlike the Silicone renders that come in ready-to-apply buckets, the mineral render needs to be mixed with water prior to application. Please follow the preperation instructions on the back of the bag before install.

                      Mineral Render is:

                      • Waterproof (once sealed with Silicone Paint)
                      • Frost-proof (once sealed with Silicone Paint)
                      • Vapour-permeable
                      • UV-resistant
                      • High grip

                      Additional Advice

                      As amazing as these products are, you still need to be sensible when choosing what conditions to work in.

                      • Always check the weather forecast, you should avoid rendering in rain, snow, and wet conditions and ideally ensure the weather the few days after the install is dry too.
                      • Never try and apply Silicone Render if the temperature is less than 5°C.
                      • Always try and protect the surfaces that are being rendered with scaffold sheeting.
                      • Always ensure surfaces are protected against wash-off, so for example the floors should be covered with Correx etc as once the Silicone render cures it is almost impossible to remove!

                      Thermal Conductivity & U-Values

                      When you start looking at solid wall insulation as a potential solution for your home or commercial premises, you may come across the terms ‘thermal conductivity’ and ‘U-value’. In this article we are going to try to shed a little light on what they both mean!

                      Thermal conductivity

                      Thermal conductivity measures the ease with which heat can travel through a material by conduction, conduction being the main form of heat transfer through insulation. Thermal conductivity is often termed the λ (lambda) value.

                      The thermal conductivity is a constant for a particular material – it is not impacted by the thickness of the material. Although when comparing different materials, products with lower thermal conductivity values are better insulators (i.e. will be better at slowing heat loss).

                      At EWI Store we sell three different types of insulation (although there are more types available in the market). The table below shows the different thermal conductivity values for these materials:

                      Insulation Material Thermal Conductivity
                      Expanded Polystyrene (EPS) 0.031 W/mK
                      Extruded Polystyrene (XPS) 0.034 W/mK
                      Rockwool Dual Density Boards 0.036 W/mK

                      So based on the lowest thermal conductivity being the best insulator, from the table above, you can see EPS is the best insulator.

                      Now – thermal conductivity is useful, but we also need to incorporate the thickness of the insulation into the calculation. The thicker the layer of insulation, the slower the rate of heat loss and also the better at retaining heat a building will be. This is where the U-value comes in. The U-value signifies the heat lost through a given thickness of a particular material. This allows you to directly compare types and thicknesses of insulation.

                      The calculation is as follows:

                      U-value = Thermal conductivity / thickness (where the thickness is measured in metres).

                      When you are comparing U-values, a lower number is better – i.e. a lower U-value signifies less heat loss through a material; therefore it is a better insulator.

                      EPS insulation

                      U-values and building regulations

                      Building regulations often provide a U-value number that needs to be achieved when building certain elements of a property. So for example when retrofitting external wall insulation on an old solid wall property, you need to achieve a U-value of 0.3W/m2K or lower. This can be achieved with any insulation material, although the thickness of the particular material will vary; for example when you are using EPS on a solid wall property, 90mm will suffice – but if you were going to use Rockwool, you would require 110mm.

                      Now, to get a true U-value figure you need to take into account all the different elements that make up the wall: the internal plasterboard, bricks or block work, insulation materials, and even the thin render top coats – they all very slightly change the u-value number.

                      So there you have it – hopefully that makes understanding U-values and thermal conductivity a little easier! If you would like us to calculate U-values to help you determine the thickness of insulation you require, then please let us know.




                      Acrylic Render vs. Mineral Render vs. Silicone Silicate Render

                      Here at EWI Store, we source our renders from EWI Pro who offer a broad range of BBA Approved renders. Whether it’s a classic Silicone Render or a traditional Monocouche render you’re after, we can cater to all requirements!

                      Nevertheless, the most popular renders within the EWI Pro catalogue are the Mineral Render, Acrylic Render, Silicone Silicate Render. As you might expect we get asked a lot what the difference is between these types of render and which is the best? Well, in this blog we thought we would try and explain the differences so you can pick the right render for your next job! If you’re looking at getting an idea of how much coloured render costs per m2, then check out our blog post which gives a really comprehensive idea of all the components.

                      Mineral Render

                      Our EWI Pro Mineral render is the only one to come as a dry mix – you need to add water to it before applying it. It also requires painting afterwards, which means it is a bit more time intensive to install. So why do people use it? Well there are a few reasons – firstly it is cheap in terms of material costs. Secondly mineral render dries much quicker than all the other types of render we offer so if you are installing in wet climates (I know most of the UK is normally under the water!) the this is the stuff to use – by the same token, this quick drying render is the one to use if you are installing in particularly humid or cold conditions since it will help minimise wash-off (when the render doesn’t stay in place due to rain or other unforeseen weather conditions!).

                      In terms of installs around the country, Mineral Render is particularly popular in both Wales and Scotland due to temperature and volume of rain. If you are doing the install yourself and it is during the summer months, the other renders just require the one coat (the colour is within the render itself) so you won’t have to paint anything once the render has been applied. Mineral render is also breathable and therefore compliments our Rockwool (Mineral Wool) insulation very well.

                      Once the Mineral Render has been applied it needs to be painted with our EWI pro Silicone paint which will provide a long lasting barrier to the elements and obviously can be coloured to your requirements.

                      Acrylic Render

                      What is Acrylic Render? Well for years has been the installers render of choice – it is essentially a render containing acrylic resin. Acrylic Resin is a type of plastic and added to render it helps offer better stain and water resistance as well as greater resistance to cracking. Our acrylic render comes pre mixed; this means that it can be applied straight on to the substrate (e.g. wall) without mixing it first with water. We sell the EWI Pro acrylic render pre mixed with your colour of choice and what is really great about it is when you opt for a vibrant colour, the acrylic render will hold this colour for a long time without fading (the other renders and the Silicone Paint will fade over time so may require painting every 10 years or so).

                      Acrylic Render is the most cost effective render when you consider the labour and material costs – requiring just one application. If you are looking for the best value system then this in our opinion is the best and certainly a huge improvement on the old sand and cement renders of the past – it is flexible and will last 20 years plus. Before you use the acrylic render though just a couple of things to consider – firstly it is not breathable. The Acrylic Resin / plastic in this render means that nothing is going to get through it, therefore it is definitely not worth putting it on a breathable insulation product like our Rockwool or Wood Fibre as it sort of defeats the point! In addition, EWI Pro Acrylic render is not worth installing when the weather isn’t very good, so cold or wet as it takes longer to dry than the Mineral Render system. Finally Acrylic render is not as resistant to the elements as our Silicone Silicate render, so there will be some maintenance required like cleaning over time.

                      Silicone Silicate Render

                      This is now our installer’s render of choice – the EWI Pro Silicone Silicate render is ready mixed (much like our Acrylic Render) and therefore can be applied straight to the substrate. It is comprised of Silicone resin and Silicate. Once installed on the wall the Silicone Silicate render is hydrophobic, which basically means it repels water and therefore can be considered self cleaning in that the water will simply run off it.

                      The Silicone Silicate render comes in a few various different textures, but by far our most popular is the 1.5mm render (read our full guide to render grain sizes). This means that within the render, it has Silicate granules just 1.5mm in diameter, so it can be applied extremely thinly on the wall – the advantage of this is that it is extremely flexible, so the house moves and the render moves with it. It simply won’t crack!!

                      Again, much like the Acrylic render we don’t advise installing this render during the harsh winter months or when it is raining as the system does take a few days to cure – but once installed it should be maintenance free for over 20 years although it make require the odd pressure spray from time to time to keep it nice and clean. The EWI Pro Silicone Silicate render is completely breathable so is the ideal partner for our mineral wool insulation products.

                      If you would like to get a quote for any of these materials try our new materials calculator by clicking on the picture below

                      All the renders we sell in the EWI Pro Insulation System range are BBA Approved –  Products that receive Agrément Certificates are recognised by building control, government departments, architects, specifiers and industry insurers. It’s a mark of quality, safety and reliability that provides reassurance that the product’s fit-for-purpose.

                      To learn more about the BBA and the EWI Pro Insulation System products please click here.

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                        Green Homes Grant Scheme and EWI Store

                        The Green Homes Grant Scheme and External Wall Insulation

                        In July 2020,  the UK Government announced a new green homes grant scheme, which is designed to give homeowners and landlords up to £5,000 of funding towards energy saving measures for their properties in England. The £2 billion scheme launched on the 30th September 2020, with external wall insulation being one of the main energy saving measures that home occupiers will be able to take-up to significantly improve the thermal comfort of homes.

                        Insulation measures are the most effective way of increasing the energy efficiency of your property. Whether this is loft, cavity or solid wall insulation. For example, installing 90mm of insulation on the external walls of your property can reduce your heating bill by 30%!

                        To qualify for the grant of up to £5,000 the improver must also contribute up to one third of the final contract costs for the works, otherwise it maybe deemed invalid




                        What happens if I cannot afford to make a personal contribution to the cost of the works?

                        If you cannot afford to make a contribution, the Government is giving up to £10,000 total support for home owners who are in the low-income group. You can then whole project fully funded and you do not need to make a personal contribution.

                        You can qualify for the Green Home Grants low-income scheme (up to £10,000 support) if you receive at least one of the following benefits:

                        • Income based Jobseekers allowance (JSA)
                        • Income based Employment & Support Allowance (ESA)
                        • Income Support (IS)
                        • Pension Guarantee Credit
                        • Working Tax Credit (WTC)
                        • Child Tax Credits (CTC)
                        • Universal Credit (UC)
                        • Disability Living Allowance (DLA)
                        • Personal Independence Payment (PIP)
                        • Attendance Allowance
                        • Carer’s Allowance
                        • Severe Disablement Allowance
                        • Industrial Injuries Disablement Benefit
                        • Contribution based Jobseekers allowance (JSA)
                        • Contribution based Employment & Support Allowance (ESA)
                        • Housing benefit

                        If you don’t receive any of these benefits then the total support will be capped at £5,000.

                        Green Homes Grant is now live and how does it work?

                        The Government launched the Green Homes Grant scheme in September. In summary here are the qualification criteria as listed on the website:

                        • you need to reside in England;
                        • be a homeowner (including long-leaseholders and shared ownership);
                        • own a park home on a residential site (including Gypsy & Traveller sites);
                        • you could be a residential landlord in the private or social rented sector (including local authorities and housing associations)

                        This scheme does not cover new build homes. It is only available to the retrofit sector.

                        To qualify for home improvements under this scheme you must install at least one primary measure, and any unused funds can then be used to part fund either a secondary or another primary measure. External wall insulation is a primary measure, therefore provided it is selected for the home improvement to improver should receive this funding.

                        For additional reading on the Green Homes Grant, this can be found on the Simple Energy Advice website found here.

                        Additional information regarding insulation measures

                        According to the scheme rules installing external solid wall insulation to a wall, you must insulate all suitable space on that wall elevation. The Government advises all the external walls to be insulated (not a requirement), but in practice you can choose 2 walls, less or more.

                        If you have a semi-detached for example and you have already insulated one or two of the walls, then you can utilise the grant to insulate the final wall. You cannot use the grant to remove and replace existing wall insulation like cavity wall insulation, but you can use the excess funds to install other insulation measures like loft or floor insulation.

                        EWI Store products are compliant with the Green Homes Grant scheme

                        It is understood, that in order to apply for the Green Homes Grant scheme, approved applicators and products will need to be used. The good news is that our external wall insulation systems are BBA approved and therefore ready for use in the scheme. Likewise we also have nationwide network of approved installers who will be able to do the works and access the £5,000 grant.

                        It is worth mentioning that the scheme is open to anyone that owns a home (including park home owners) – however the property must be based in England to be eligbile. The Grant is non-means-tested, so provided you own the property you are good to apply!

                        EWI Pro External Wall Insulation Systems

                        EWI Store offer a wide range of EWI Pro External Wall Insulation Systems. EWI Pro are a system designer and manufacturer, prodcuing specialist external insulation and thin coat render systems.

                        EWI Pro Insulation Systems has two systems that are certified to the BBA, which are the EPS EWI System and the Mineral Wool EWI System. The BBA is the British Board of agreement and certifies the products and systems, so they are “fit-for-purpose” for the retrofit improvements that are being recommended.

                        In their testing of the systems, the BBA carries out a set of robust tests that examine the products for their longevity, fire resistance, water penetration and many more. All the products and systems are rigorously tested in the respective factories that produce them so that the quality control in maintained at all times.

                        Basically, you can rest assured that if you do decide to use the EWI Pro family of products for your next project, they are some of the best available on the market!

                        All the Materials you need we can supply!

                        If you want to know the benefits of using Rockwool Insulation over EPS then check out our blog ‘Why use Rockwool in your EWI System?‘ or ‘The Advantages of Rockwool Insulation‘.

                        How Do I Apply?

                        Step 1: Go to the Simple Energy Advice (SEA) website to check what low carbon or energy efficiency heat improvements can be made to your home.

                        Step 2: Contact us at EWI Store so that we can find you a local accredited installer and give you price quotes.

                        Step 3: Apply for the voucher on the Government website

                        Contact us for more information

                          CALL US:

                          Chessington Branch: 02033 974067

                          Aylesbury Branch: 01296 821067

                          EMAIL US:

                          Sales Enquiries: [email protected]

                          Technical Enquiries: [email protected]

                          Are you an Installer?

                          Check out our Green Homes Grant Scheme blog for Installers.

                          Why use Fibreglass Mesh in Render Systems?

                          Fibreglass Mesh is an essential component of our render systems. It helps to provide strength and flexibility to our thin coat render systems, ensuring that the render remains crack resistant for years to come.

                          Fibreglass Mesh is made of neatly woven fibreglass thread. This type of mesh is widely used in plastering and rendering for wall reinforcement, external wall insulation and roof waterproofing. We offer different weights of mesh depending on the intended use and, typically, heavier mesh provides more impact resistance within the render system. At EWI Store, the heaviest mesh we sell is our Panzer Mesh at 350g/mand this is often used in areas that are likely to endure heavy impacts e.g. a wall where a football is kicked against it.

                          All of the mesh we sell is alkali-resistant. This helps prevent it from being broken down by the chemicals in the other mortars and adhesive materials.

                          Where do you put the Fibreglass Mesh in render systems?

                          The Fibreglass Mesh is embedded within the basecoat layer within both render and external wall insulation systems. The mesh needs to be embedded within the basecoat while it is still wet, and we always recommend getting the mesh embedded within the middle of the layer of the basecoat, rather than too close to the surface or sitting right next to the wall.

                          In thin coat render systems, the basecoat thickness is normally between 4-8mm, so installers tend to have different embedding techniques.

                          A notched trowel can be used to apply the basecoat to the wall at the required thickness and then the mesh can be tapped into the basecoat. A straight-edged trowel can then be used to ‘pull’ the adhesive through the mesh by applying pressure to the basecoat.

                          Other installers will apply a thinner first pass of adhesive, then tap the mesh in place, then apply a second layer of the basecoat. Either method is absolutely fine however, if you do go with the second method, ensure the first pass of basecoat has not dried before applying the second pass of mesh; the mesh needs to be embedded within a fully wet product.

                          Overlapping mesh in basecoat

                          During weather and temperature changes, the external walls of your home expand and contract minutely due to the heating and cooling processes. Mesh is used to help the system ‘flex’ with these building movements to help prevent cracking. 

                          All our mesh comes with markings 100mm from each end. This marking illustrates the overlap of the mesh required when installing it. Each strip of the mesh needs to overlap the last by 100mm otherwise cracks can appear in this area over time.

                          The mesh provides additional strength to all thin coat render systems and helps prevent cracking, so we highly recommend it if you want to ensure the structural stability of your system!

                          Below is an example of a buildup for Render-Only on a brick substrate which demonstrates where the Fibreglass Mesh fits into the process. 

                          To see how we test the strength of our Silicone render system with and without mesh, please watch our YouTube video “Silicone Render Impact Test“.


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                            The Importance of Render Repair

                            Our homes are precious to us, our first consideration is most often an aesthetic one. If it looks bad why would we want it? The outer layer of your property- the first thing you see is the render, so this plays an important part in defining the shape and appearance of your home. Cracks are unsightly anyway but repairing these will have a massive and satisfying trans-formative impact. Not only visually but will help your render last longer and will keep it weatherproof.

                            Homes are, to many, an extension of themselves. So, what happens when the exterior of your home has been looking a bit lackluster recently? Your home may need a bath! One of the best ways to clean your rendered home is to use a pressure washer with a mild detergent, just be careful to adjust the settings on your pressure washer to a fan setting to avoid etching and damaging your render surface. This will help if your home is looking a bit grubby.

                            Just like any building material, Render will need maintenance and repair occasionally. Certain factors can result in the render cracking and separating from the wall. After a while organic growth can affect your render too, early stages of organic growth results in green and red staining on your render.

                            If your render has been invaded by moss and algae, then you should consider applying a good moss and algae killer. Algae is one of the oldest organisms on earth and tends to be the first organic growth to show up on your home. It will feed on the moisture and minerals on the substrate. If it reaches this stage, then your home may need specialist treatments to remove it. Garden centre biocides will not be powerful enough to remove the algae on its own.

                            If you are new to Render and haven’t yet rendered your home then you should consider EWI-076 Premium Bio Silicone Render if organic growth is a concern of yours. This render has an advanced resistance to algae and plant growth.

                            What about cracked Render?

                            Have you ever walked past a crusty old looking house that has cracked and stained render? This extent of damage is avoidable by maintaining and repairing the rendered finish. Not only is this unsightly but poses massive concern for the brickwork beneath.

                            Even small cracks in your render can create a pathway behind the render and allow water to penetrate between the render and brickwork. The water will eventually penetrate the brickwork and will create damp areas in your internal wall.

                            This will create ugly damp marks in your home, but can also lead to mould growth, which could affect your health, especially if you already have underlying health conditions.

                            Water ingress in your brickwork will also cause problems in the winter months. This is because of a process known as ‘freeze-thaw damage’. This is because as water freezes it also expands, which causes the bond between your render and brickwork to blow. The result is your render no longer being bonded to your wall; render may start to flake off from your walls. This can also lead to damage to your underlying brickwork.

                            To fix hairline cracks paint may be enough but for thicker cracks you will need to use thicker products. For example you can try the EWI-051 Fin Plast if it is sand and cement or you could use the EWI-225 if it is silicone or acrylic. You should add a strip of mesh on the top like a plaster and then when it is dried, you should feather in the acrylic or silicone render. If you are not comfortable in filling these yourselves, then there are many professional services to choose from. Fill in our survey at and we will help you find a suitable installer.

                            What can cause cracked render?

                            Your home expands in the summer and compresses in the summer. This means if your render does not have enough flexibility to allow for this movement then cracks may occur. You can reduce the chances of this occurring by choosing a silicone-based render because it is the most flexible. Depending on the type of render on your property, this may not be avoidable. This is because certain circumstances may exasperate the movement of your home.

                            Things like having heavy work/ renovation done- the vibrations from drilling can cause your render to have hairline cracks. Other things that may contribute to cracking in your render could be foundation and subsidence issues or if you have a new build property. This is because new builds tend to take a few years to settle in.

                            Another thing to make sure of when rendering your property, is that it is applied properly. Application errors can also cause cracks to form or your render to separate from the substrate.

                            Do I need to do render maintenance?

                            It is extremely important to maintain your property. Render has a tolerance and is weather resistant, but if you do not address problems as they appear then they can take a toll on your render. Making sure you maintain your gutters or fixing any leaks is an important step in maintaining your render.


                            Can You K-Rend Over Painted Render?

                            What is K-rend?

                            People often confuse ‘K rend’ as a product but ‘K rend’ is in fact a brand that has a large range of render products. These products are manufactured by a company called ‘Kilwaughter’ which is the chemical manufacturer parent company based in Northern Ireland.

                            What renders do they offer?

                            They offer a range of FT one coat topcoats, this topcoat is a cement based, polymer modified render. Having silicone as a component of this product enables it to have higher water repellency, which in turn means that less dirt will be able to adhere to the surface, meaning it will be clean for longer and lower maintenance than other types of render. This offers similar properties to other silicone-based topcoats for example, although not cement based, EWI Pro’s EWI-075 Silicone render will offer you long lasting results, a self-cleaning and low maintenance finish.  Enewall fine scratch render is very similar to the K-rend FT 1 scrape render in all aspects so may be a good alternative.

                            Can you k-rend over painted render?

                            So, you want to K rend your home, but you already have old painted render that would be costly to remove. So, what are your options, and can you just render over the top?

                            The answer is yes technically, however there are certain things you need to be wary of. K rend is a heavy product so whether its suitable or not depends on the weight of your original paint. If the original paint on your wall is too heavy and not very strong then everything will just fall off the wall. This means you need your installer to analyse and test your current paint to ensure they are comfortable in rendering over the top without worrying about paint peeling off.


                            To help avoid this we do sell a primer called EWI-310. Using this primer will help to secure the new K rend to the wall however the primer can only do so much and does not replace a substrate in good condition. If the paint is too smooth, then you may need to use a primer with grit. you can use ‘scrim and pin’ fixings to help tie the new render to the wall – these are basically fixings that go through the existing render and into the brick / block beneath, but it isn’t ideal solution. Likewise, you could apply insulation and anchor that to the wall, then apply a thin coat render system (K-rend’s TC15 or EWI Pro EWI-075) but if the painted render is too weak then ideally it needs to be removed despite the extra labour costs this will incur, in the long run this will save you money in repairs if your render does end up coming off from the walls.


                            Different Methods to K- rend over painted render

                            If your home is already rendered and painted, then you can choose to remove this layer first before adding new render. This option can be costly as you will incur more labour costs during the removal process and can cause damage to the brick or block work beneath. To help with these damages after removal, you can apply and install a base-coat. EWI Pro’s EWI – 225 Is a good option for this. First install the EWI-225 base-coat and then embed some fibreglass mesh to support the base-coat. With the base-coat your K-rend does not need to be as thick so you can apply it 10-11mm thick and once dry scratch it down (using a render scratching float) to 8mm thick.

                            If the paint on your wall is stable enough then you can apply the K-rend straight onto the wall. You can apply 18mm and once dry you scrape down to 15mm. Most installers choose to apply this in two stages as the weight of the product can cause it to sag. On day 1 they would apply up to 10mm, embedding fibreglass mesh in between and then the next day applying a further 8mm. They would then scratch this down. You can choose to apply the product using a spray machine or by hand.


                            The Importance of Corner Beading in Rendering

                            Corner bead is used on all external corners on render-only systems. It is a pretty important component of the render/external wall insulation system and in this blog we look at what it is, where it is used and why!

                            What are corner beads?

                            Corner beads tend to be made from rigid PVC, moulded into a 90-degree angle. The PVC has lots of holes within it so when it is embedded with the adhesive, the adhesive can travel through it and completely immerse the corner beads, helping to hold them in place. Sometimes corner beads come with mesh wings attached to the rigid PVC; these can be covered with adhesive, again helping to keep the corner beads in place.

                            At EWI Store we offer several different types of corner beads, depending on the situation and the type of render being used. Our main corner beads are either:

                            • For use in thin coat render systems (the corner beads are completely buried within the thin cost render system). These come with or without mesh wings attached to the PVC.

                            • For use in monocouche scratch render systems (beads protrudes out of the render on the corner).

                            The above example is the EWI-65520, it is mesh,  it has no nose and is 2.5m in length.

                            What is the reason for using corner beads?

                            Corner beads are used in render systems for 2 main reasons:

                            • Corner beads reinforce and protect external corners – this includes around windows and doors, as well as at the corner of the property.

                            • Corner beads provide a nice sharp finish when rendering.

                            Corner beads add an extra layer of protection for external corners, which often take a lot of knocks. The layer of impact-resistant plastic provided by corner beads reinforce stress points and allows render to be flexible without cracking. It is amazing the number of knocks that the corners of buildings take. Using corner beads ensure that even if knocks do occur, then the system will be able to withstand the impact.

                            Corner beads are also used to provide sharp 90-degree angles on the corners of buildings. Trying to free form a 90-degree angle is difficult and although some renders decide not to use corner beads, we would never advise it! Corner beads are relatively cheap in the scheme of things and so it makes sense to use them to ensure you can get that perfect angle on the property!

                            Above is a Flexible Arch Bead, it is the EWI-66500, it has no mesh and is 2.5m in length. This bead easily bends to reinforce curves and arch forms. The Arch Bead fixes to the profile of the curve, giving you a smooth strong finish.

                            How do you embed corner bead?

                            If using a thin coat render system, then corner beads are embedded using either the EWI-220 Adhesive or the EWI-225 Premium Adhesive. It is completely embedded within the adhesive/basecoat layer, but be sure not to wrap the basecoat mesh around the corner – instead run the mesh up to the rigid PVC moulded plastic. This ensures you don’t ‘round’ the corner when installing the corner bead. For a visual demonstration of this process please watch our YouTube video “EWI-220 EPS Basecoat Application”.

                            Above is an example of a corner bead that you would use for monocouche scratch render systems. The above example is the EWI-63300, it has a 6mm nose (that part that will protrude out of render), no mesh and is 2.5m in length.

                            With monocouche scratch render, the scratch render is taken up to the corner of the bead, but the bead still shows through the render. You can therefore get different colours of monocouche scratch render corner bead – get in touch for options!

                            Above is the EWI-65620, this type of bead is shown in the linked demonstration video above. It is also known as a Panzer corner bead. This bead is used for internal corners, it has extra strength for additional movement and is used for both external wall insulation and render only.

                            Corner beads make your life easier during installation, increases the lifespan of the system and gives a better looking final result – so make sure to use them when rendering or installing EWI systems!

                            Is K Rend a System or a Product?

                            What is render?
                            Render is applied on external walls to seal them off against harsh weather conditions, or an opportunity to give your property a face-lift. Early rendering was a messy business, slapped on the walls using sand and cement and finished with coloured paint. Over the years, render technology has evolved greatly, giving a much larger choice of colours and finishes -enabling tailoring to specific environments.

                            For instance, hydrophobic renders can protect properties in damp environments from water penetration and weathering. Also, the renders contain flexible polymers, helping the surface retain its structure without cracking very easily.

                            Traditional render is subject to wear and tear and if not regularly maintained and repaired, can leave the building in an awful condition. Cracks may appear on older render systems, which may then cause damp and water penetration.
                            The thinner coat renders tend to use fewer bags material , which is why in most cases they have a tendency to be less expensive to install than thick coat renders.

                            What is K Rend?

                            K Rend‘ is often used in the external insulation business as a catch-all term for render. Just as the personal cassette player was most known as the ‘Walkman’ throughout most of the 1980’s and 1990’s, K Rend has the similar brand recognition.

                            K Rend in fact is ‘only’ a brand with a large range of various renders, manufactured by Kilwaughter, the chemical manufacturer parent company in Northern Ireland. K Rend traditionally produced ‘thick coat’ renders like dash receivers and Monocouche and has recently also ventured into the family of silicone render products.

                            K Rend render is a water-repellent, breathable solution – low maintenance and available in most colours.

                            Despite its reputation, it is only one brand amongst several external rendering products within the market. There are dozens of other systems that can be sourced and installed that do the same job.

                            What is the difference between K Rend and other render manufacturers?

                            As mentioned, K Rend traditionally manufactured traditional English thick coat renders, whilst in Europe thin coat flexible renders were significantly more popular. Over the years, various acrylic and silicone thin coat solutions have made it to these shores and are now growing in popularity. Several houses have been successfully retrofitted with these solutions.

                            Whilst K Rend also produces thin silicone renders, the European manufacturers probably have a longer history of using thinner coat products. However, K Rend stands up well against competitors’ products.

                            Both K Rend and other manufacturers now specify a flexible bead or mesh inserted into the base coat adhesive before the final layer of render is applied. However, since K Rend does not have a full external wall insulation system, beading is optional where it is mandatory on many other render systems. It is our view that the more flexible the render layer, the longer its lifespan, because it will be less susceptible to movement and surface cracking.

                            Does K Rend offer an external wall insulation solution?

                            Whilst K Rend can be used as the render based system on top of insulation, the brand itself does not have a certificate for an external wall insulation system (ETICS). This contrasts with many of the thin coat systems, which also come together with the external insulation system.

                            More and more, older homes are not just going through the re-rendering process, but homeowners are also upgrading the thermal efficiency of their properties as well as updating the render at the same time. It is a less expensive way to re-render, as with external insulation the homeowner or occupier should look to understand that heat cost savings over time would go some way to pay for the cost of the job.

                            K Rend and other render brands

                            We believe that certain renders will work in certain situations. For example, many properties in South Wales and Western Scotland are pebble-dashed and the K Rend offers the perfect solution to repeat this process. Also, some architects may specify Monocouche thick render scratch finish, and in these cases, it is reasonable to want to go for the K Rend system.

                            Just be aware there are other render manufacturers also exist which offer similar products to K-rend like EWI Pro Insulation Systems, Johnstones and Sto.

                            Why Use External Wall Insulation?

                            Externally insulating your home will reduce the amount of heat escaping through your walls, hence will save you money on your heating bill. This also means your home will warm up faster, last longer and reduce carbon emissions.

                            As a result of keeping your walls warm and dry, the External wall insulation can protect the houses structure and improve it’s weatherproofing, which will in-turn prevent damage and keep your home looking fresh for longer.

                            With different insulation solutions available, why should you use external wall insulation?

                            External wall insulation can be applied with a variety of decorative finishes. This means that not only are you insulating your home, you are also altering and improving its aesthetics. When externally insulating your home, you can choose between a multitude of different colours and several different textures.

                            Externally insulating your home will cause some disruption, however when you compare this to the disruption caused by Internally insulating your home it is significantly less and wont reduce the size of your rooms, unlike Internal wall insulation.

                            Disadvantages of Internal wall insulation

                            Internal wall insulation also comes with additional risks and limitations over External wall insulation. For one it is less effective than External wall insulation and does not offer the same protective qualities. Internal wall insulation can make securing things to walls difficult. Stud walls are capable of holding heaving fittings, but if you have used insulation boards, the fittings need to be able to penetrate through them, then into the wall behind.

                            As discussed above this method also reduces the size of your room. The thicker you insulate your home the smaller your rooms will become. This means you are limited in the extent you can insulate your home.

                            Using Internal wall insulation means your home is far more likely to be affected with damp problems. Wet rot and mould can build up quickly on the inside of the masonry (the face that the insulation is fixed to) This can create hazardous spores, which will be breathed in by the occupants, and has the potential to create, or exacerbate existing health problems.

                            Another major concern when dealing with Internal wall insulation, is that a sufficient amount of warmth will not pass through the insulation and into the dwelling, (which normally keeps your walls dry) this means your walls will become damp and water ingress can turn to frost and damage your brick work, a process known as ‘freeze thaw damage’.

                            Disadvantages of External wall insulation

                            There are few reasons against External wall insulation especially when compared to Internal wall insulation. Some of the reasons may be purely aesthetic, for example if you are fond of your brick work. This is because by externally insulating your home, you are covering the outside of your house with insulation materials, that will need rendering to create a polished and protective Finnish.

                            If you live in a flat this may also not be a realistic option, as the insulation would not be effective without also insulating the rest of the block. This is often not possible so in this instance you may turn to Internal wall insulation.

                            In some cases you may also need to be granted planning permission from your local council, to have your home externally insulated, so in this case you may also need to consider Internal wall insulation. In most cases we would recommend External wall insulation unless you are included in the above examples.

                            What Insulation Materials can be used for External wall insulation?

                            there are a lot of suitable materials for this procedure, so you will not feel limited for choice! You can choose between EPS, Kingspan, phenolic resin, wood-fibre, cork and mineral wool. You may decide to use EPS (expanded polystyrene) as this is a popular option, and is one of the most cost effective materials.

                            External wall insulation must abide by strict building regulations, which will have an affect on the material you choose. Solid wall insulation needs to have a U-value of 0.30 watts/m2k. The down side of EPS is that it requires a thicker amount of this material to achieve the same thermal performance/ U-value compared to Kingspan.

                            Mineral wool may be your preferred choice because by nature Mineral wool is moisture-resistant, and it is able to keep its insulating properties even when wet. Mineral wool is also good at blocking sound so means your building will have less acoustic invasion.

                            One of the best advantages of this material is its heat-resistant qualities- It will not burn until the temperature goes above 1000°C. Just ensure if you chose Mineral wool that you do not use an Acrylic render to Finnish, due to its lack of breath-ability, compared to the Mineral wool which will defeat the purpose of using Mineral wool in the first place.

                            Wood-fibre is a fantastic option as it is the most breathable, and natural insulation material, however this system is very pricey compared to the EPS system.

                            How To Cover Up Old Pebbledash

                            How do I get rid of pebbledash?  

                            Pebbledash became extremely popular in the 1920s due to an increase in demand for homes to be built. This lead to builders cutting costs and used pebble-dash to cover up poor brickwork. At present, this has resulted in an outdated and, for many, unsightly look that many homeowners are looking to remove. 

                            If the right materials aren’t accessible, re-rendering pebbledash without removing the pebbledash can be difficult. Removing pebbledash is a painful process because removing the render requires hard work with a hammer and chisel, with the added risk of damaging the original brickwork. Typically, pebbledash is made from a sand and cement render: an incredibly unforgiving material that was often applied as a means of covering up a bad build job.

                            With the growing popularity of coloured render, pebbledash has taken a bit of a hit of late, with pebbledashed house prices falling to reflect a national dislike. Nonetheless, as long as the pebbledash is in good condition, there is no reason this can’t be rectified without the expensive process of removing it.



                            How to re-render pebbledash without removal

                            So, how do you re-render pebbledash without removing the pebbledash render? There are a couple of ways you can do this which we are going to explore…


                            1. Smoothing over the pebble-dash with One Coat Dash Cover (OCDC)

                            One of the best ways of re-rendering pebbledash without removing pebbledash render is by smoothing over it with our One Coat Dash Cover (OCDC). This is the ideal material to use because it can be applied at a thickness of 20mm without compromising structural integrity. You wouldn’t want to put a non-breathable material on top of the pebbledash because water needs to be able to escape from the walls, otherwise, you may find yourself in an unpleasant, waterlogged situation.

                            The first step in re-rendering your pebbledash is to ensure that any loose stones are rubbed off.

                            The next step is to prime the pebbledash using the 310 Universal Primer. This will limit the absorptive capacity of the pebbledash render and ensure that any dust is settled; it also provides a good grip for the basecoat to adhere to.

                            Once the primer has been left to set for 12 hours, you can go ahead and start preparing the OCDC for application. One 25kg bag needs to be mixed with 5 litres of clean water, using an electric paddle mix. Once mixed, leave for 2-3 minutes before re-mixing and then apply to the substrate using a plastering trowel. We recommend embedding Fibreglass Mesh within the basecoat, overlapping each strip by 10cm to ensure crack resistance and tensile strength.

                            Once the initial coat of 5-20mm has set, apply a ‘tight coat’ using a plastic, metal or felted float. After this has set, we advise applying a thin coat render such as Silicone Render; this is highly breathable and is available in a wide range of colours, so will provide an aesthetically pleasing finish. To learn more about this technique please check out our YouTube video ‘One Coat Dash Cover’.


                            2.Externally insulating on top of the pebbledash

                            Another method of re-rendering pebbledash without removing pebbledash render is to apply insulation boards to the existing pebbledash. Even 20mm of EPS insulation secured to the exterior of the property can increase its thermal efficiency and create a smooth surface for a fresh layer of render to be applied to. The method of preparation is the same: any loose pebbles should be removed and the wall should be primed with the Universal Primer.

                            The insulation boards should then be secured to the substrate using the 225 Premium Basecoat. This should be applied to the whole of the back of the insulation boards – we don’t recommend doing the dot and dab method for applying insulation to pebble-dash. Mechanical fixings should also be used to secure the insulation boards to the pebbledash.

                            Once the boards are set in place, you should have essentially created a new substrate for re-rendering pebble-dash without removing pebble-dash. The best practice is to rasp to EPS to achieve a smooth surface and remove the oily top layer, and then you can apply your render basecoat. We recommend using the Premium Basecoat for extra strength, embedding fibreglass mesh within the basecoat to ensure a strong and stable surface for the render. Finally, you can prime the basecoat using the SiSi Render Primer, leaving it to dry for 12 hours before applying either the Silicone or Silicone Silicate render.

                            And there you have it! Two easy ways to re-render pebbledash without removing the pebbledash render.







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                              The Benefits Of Using Silicone Render

                              Why render my home?

                              So, first things first, what are the benefits or rendering your home? Rendering your home has many advantages, from protecting the brickwork from damp and damage, to modernising the outside aesthetics of your house. Rendering your home may also offer another layer of insulation, keeping your home warmer in the winter months and reducing energy bills.

                              There are many different types of render such as Cement Renders, Lime Renders, Polymer based Renders, Monocouche Renders, Acrylic Renders, and Silicone renders.

                              What is so great about silicone renders?

                              Silicone renders are growing in popularity due their unique properties over other types of render. Silicone renders are breathable, flexible, hydrophobic, and self-cleaning!

                              The breath-ability of you render is important because it means that if moisture ever manages to get behind your render, it will be able to get out again, whereas if your render was not breathable, the moisture would stay behind the render, and potentially cause damage to your walls and render.

                              Houses tend to swell in the summer and shrink in the winter months which can cause your render to crack. Cracking is not just worrisome for aesthetic reasons as cracks will create a moisture pathway for rain and moisture to get behind the render system. Once there, moisture can penetrate deeper and cause further cracking. The flexibility that silicone render offers, means that it is very resistant to cracking, more so than any other render and will stand the test of time.

                              As stated above, having moisture penetrate through your render can cause serious problems and damage, but luckily Silicone render is extremely waterproof. This causes water to bead up on the surface, and once this bead is heavy enough to run down, it will take dirt with it , meaning it is also self-cleaning! this will keep your render looking fresh long term.

                              Some silicone render products also contain cleaning agents which attack bio-growth like the ‘EWIPRO Premium Bio Silicone Render‘ which is ideal in high vegetation areas or areas with increased exposure to organic matter. This prevents bio-growth and keeps the render looking clean and fresh for longer.

                              Silicone renders come in a wide range of colours and grain sizes. This enables you to choose what textured finish you want. Thin coat renders can be applied to a thickness of 1mm -3mm which offers maximum flexibility and breath-ability. Coloured render enables you choose between more subtle or bold colours. With all these options you can customise your property the way you want it.

                              Silicone render is one of the newest and best performing renders which is reflected in the price as it is slightly more costly than the other types of render, however we would definitely recommend it because of its low maintenance and long lasting properties will save you time and money in the future. Silicone renders have a life expectancy of around 25 – 30 years depending on the quality of application.

                              Silicone renders come pre-mixed which means that the product will always be mixed to a consistent ratio and wont vary from pot to pot. Silicone render is also one of the easiest renders to apply. This product has a lot to offer for both ease of application and for quality and appearance.