Tag Archives: render

How to achieve a brick-like finish on your EWI system: Brick slips

Are you fascinated by all the environmental benefits of external wall insulation, such as improved thermal performance, reduced energy bills and increased façade durability, but having doubts because you don’t want to let go of that beautiful brick aesthetic on your home? Then, brick slips are the product for you. While silicone render is available in several different grain sizes and thousands of different colours to allow you to create a personalised finish, you can instead choose brick slips as the final stage of your external wall insulation system – which are also available in various colours – to receive all the benefits of a system whilst enjoying the traditional aesthetic of exposed brickwork. If this sounds more like you, and you want to know more about brick slips, keep reading!

What are brick slips?

Brick slips are thin, acrylic tiles that are predominantly manufactured and cut from real reclaimed bricks. Much like a brick wall which is created by building brick upon brick, brick slips are applied to the wall one by one atop the adhesive to mimic real brickwork. They are highly flexible, meaning they can bend around corners to recreate the edges of bricks, and available in various natural colours and textures, again much like real brick. Brick slips can be applied both internally and externally but have grown in popularity as the final stage of an external wall insulation system to receive the benefits of external wall insulation without letting go of the traditional brick aesthetic.

Brick slips provide further benefits to an external wall insulation system if you live in an area where there is a high risk of mechanical impact such as on a busy road. Due to their brick-like nature, they have a great ability to withstand damage from mechanical impact and are very hard-wearing. They are also weatherproof and UV-resistant, meaning their colour won’t fade over time. So, if your current brickwork is looking a little tired, brick slips – along with the added benefits of external wall insulation – are the way to go.

How are brick slips installed?

Our brick slips are extremely simple to install. We offer a special adhesive that comes in five different colours and is specifically designed for use with the brick slips to create a long-lasting, reliable bond between the brick slips and the substrate. The adhesive is the most important part of the installation process as it will ensure the solidity of the installation.

When installing brick slips on top of an external wall insulation system, you must first install the basecoat and mesh on top of the insulation boards. Then, the special brick slip adhesive must be applied using a notched trowel. Following this, the brick slips can be applied to the adhesive in the form of a standard brick pattern, staggering the bricks and leaving a space of around 10mm between each brick both vertically and horizontally. As mentioned earlier, the bricks can be bent around corners owing to their flexibility, or you can cut them to your desired shapes.

What are the different types of brick slips?

Here at EWI Store, we offer several types of brick slips to cater to every taste:

  • Bavarian Castle. Our Bavarian Castle brick slips are of a beautifully clean and modern light grey colour which offer a noticeably fantastic facelift to any home. Their colour also offers an excellent contrast to wooden doors and window frames for a modern look with a traditional touch.
  • Cedar Hill. Our Cedar Hill brick slips offer a more conventional aesthetic, combining hints of dark red and brown, as you would imagine real brickwork to look. The Cedar Hill brick slips are perfect if you are seeking to achieve a traditional look whilst updating the look of your home.
  • Charcoal. Bold and modern, our Charcoal brick slips are the perfect solution if you are looking to make your house stand out from the crowd. The Charcoal brick slips will look fantastic when combined with white windows and doors.
  • Yellow Stock. If you are looking to brighten the façade of your home in an understated fashion, Yellow Stock brick slips are the ones for you. These brick slips look excellent all year round and remain timeless.
  • Siberian White. Bright and modern, our Siberian White brick slips are a fantastic option if you are seeking a complete refresh of the façade of your home. White will work with any colour of doors and window frames; white for a clean finish, and black or any other colour to create a contrast.
  • Wentworth Mixture. Similarly to Cedar Hill, our Wentworth Mixture brick slips mimic the appearance of traditional bricks owing to their natural red-brown colour. Whether you already looking to update your current brickwork or are for an understated look, Wentworth is for you.
  • Westminster. Our Westminster brick slips offer a bright, natural aesthetic with their neutral stone-like colour adorned with hints of red and black. Like Yellow Stock, Westminster provides a timeless look whilst giving your whole home a facelift.

So, if brickwork is to your taste and external wall insulation sounds like an excellent solution for you, then brick slips are the option for you! As you can see, our range of brick slips means that we can cater to every taste, allowing you to achieve your desired brick-look finish. If you have any questions about our brick slips and how they work with external wall insulation, please do not hesitate to contact our talented Sales Team who will be happy to help!


How to clean and maintain your render

If it’s been a while since your house was rendered, you might be thinking that it looks like it needs a little clean. If so, you’re probably right: over time, it’s only inevitable that the façade of your home will begin to look a little dirty, dreary and dull, especially if you’re in a high-exposure area. By that, we mean your home is exposed to excess levels of wind-driven rain, causing the development of dampness, algae growth and mould. So, if you have noticed any black or green markings on your home, how do you go about cleaning it? It all depends on the type of render you already have on your home. In this blog, we’re going to cover how to clean off dirt alone, how to clean before painting and how to clean before re-rendering your home.

How to clean dirt, mould and algae growth off your render

If your house is just looking a bit grubby, it might simply need a wash-down. This can first be achieved by soaking a cloth in soapy water and wiping the surface area. If this hasn’t quite done the trick, you can go a little further by using a pressure washer with a mild detergent; however, be sure to adjust the settings to a fan-spray setting to avoid etching and damaging the render.

Alternatively, if your render façade has developed mould and algae growth, you should consider using a moss or algae killer. One of the oldest organisms on earth, algae tend to be the first organic growth to show up on your home; the longer it remains on the render surface, the more it will feed on the moisture and minerals within the surface. If it has reached this point and the amount of algae growth is excessive, you may need to hire a specialist to remove it for you; garden centre biocides are simply not powerful enough to remove the algae on their own.

Owing to its self-cleaning properties, our Silicone Render effectively resists organic growth and therefore requires very little maintenance over the course of its lifetime. Nonetheless, lighter colours are more likely to be susceptible to showing dirt; in this case, the best method for cleaning the render is to use soapy water and a sponge as and when. We offer thousands of colours for our Silicone Render; from calm and neutral to bright and vibrant, you can have any colour you like and, if you clean it as and when, it will remain looking fresh for years to come! If this sounds appealing, take a look at our Coloured Render Sample Pots.

How to clean your render before painting it

If you’re looking to paint or repaint your render, you can follow the same steps as above to clean it in preparation for the paint coat. It’s vital to ensure that it is cleaned properly to avoid any dirt, mould or algae growth from seeping through the paint and causing further issues down the line.

Once your render façade is cleaned properly, you’re going to want to choose a long-lasting, self-cleaning paint to, again, prevent issues regarding dirt and algae growth down the line. Our Silicone Paint is a high-performing masonry paint that is designed to be painted over an existing render to refresh the façade.

How to maintain your render

If you’ve recently had your home rendered – or you’re looking to have it rendered – with one of our specialist Silicone Renders, you’re in good hands; as mentioned, thanks to their self-cleaning properties in addition to their advanced flexibility, our Silicone Renders are designed to last for years to come. Nonetheless, if organic growth is your biggest concern, our Premium Bio Silicone Render is the render for you. What sets this render apart from others in our collection is its ability to actively break down signs of organic growth due to its enhanced vapour permeability. Again, this render can be tinted to absolutely any colour of your choice, including any RAL, NCS or Pantone tones; so, not only does it guarantee an aesthetically pleasing finish, but a long-lasting solution for your render façade!

If this isn’t enough, or you’re in a high-exposure area, you can enhance the protection of your home with our Nano Drex Protect – Render Guard. This product is designed to create a breathable barrier to prevent organic growth, discolouration and water ingress, prolonging the render façade’s lifespan even further – what more could you want?!

The main features of Nano Drex Protect include:

  • its hydro-protect formula;
  • it’s long-lasting;
  • it’s easy to apply;
  • it’s freezeproof; and
  • it’s vapour permeable.

Before applying Nano Drex Protect, as you would when painting or repainting, ensure that the render is cleared of dirt and anything that might reduce the contact between the product and the render. Any surface covered in mould, organic growth or moss should first be treated with EWI-360 Fungicidal Wash, which takes just 24 hours to kill all microorganisms on the substrate.

Get in touch

Interested in rendering or re-rendering your home, or wondering how to go about cleaning its façade? Our experienced Sales Team will be happy to assist with any enquiries you may have! Find our contact details here.

EWI Store are the leading UK render specialists, offering a range of high-quality Render and External Wall Insulation products. We take a whole-system approach to external wall insulation, stocking all the materials required to help installers achieve a stand-out result. Our selection of products is constantly growing as we strive to offer our customers the best possible choice of materials from trusted manufacturers and established brand names.

Looking to render over pebbledash? Try OCDC and Silicone Render

Calling all pebbledash property owners! Looking for a way to spruce up the look of your home? Then you’re in the right place. Here at EWI Store, we offer various solutions for enhancing the aesthetics of any building, all while improving their thermal comfort, environmental performance and, ultimately, energy bills. We’re often asked how to best rid that outdated, dull pebbledash façade; as pebbledash removal can be extremely time-consuming and – not to mention – damaging to the property, it’s best to cover it entirely with a new render façade. In this blog, we’re going to explain exactly how you can go about covering pebbledash.

What is pebbledash?

Pebbledash, or roughcast, is a form of render consisting of a layer of mortar – typically sand and cement – and pebbles that are thrown onto the mortar while wet. It derived as a way to conceal the cheap-looking bricks that were made to build houses, but you will still find it on a plethora of properties up and down the country today. Arguably, the only benefit of pebbledash is that it is extremely durable; otherwise, especially in the UK, it is largely considered outdated, unappealing and, as such, an unpopular render choice.

Can you remove pebbledash?

Technically, you can remove pebbledash by hacking it off. However, not only will this inevitably damage the property, but there is no guarantee that it will achieve a nice, smooth finish. Due to its slap-dash nature, as you try to hack off stones, you will also inevitably hack off the mortar they are stuck to, exposing the underlying brickwork. Plus, after hacking it off, you would still need to apply external wall insulation before applying render to comply with building regulations.

So, can you render over pebbledash?

Absolutely! There are a couple of ways to render over pebbledash; one option is to apply OCDC over pebbledash. OCDC is specifically designed to be applied on top of pebbledash and can then be painted or rendered on top to achieve a smooth, modern look. OCDC is highly breathable, meaning it will allow any trapped moisture within the underlying pebbledash to escape. It can also be applied up to 25mm in one pass, therefore up to a maximum of 50mm after two coats, so it’s guaranteed to smooth over the pebbledash nicely and deliver a fresh, modern façade. Whether you’ve just bought a pebbledashed property or your existing pebbledash looks tattered, OCDC provides a solution for you.

What if I like the pebbledash aesthetic?

Well, for one: that’s a unique taste you have as pebbledash is certainly not a popular render choice anymore, but that’s okay. If your pebbledash aesthetic is looking tired and dull, but you are keen to update it, then you could have your property re-rendered with pebbledash. However, we have a much better option for you…

Replacing Pebbledash with Silicone Render 3mm

As mentioned earlier, another way to rid that pebbledash look on your home is to apply external wall insulation, then render over it. Nonetheless, if you are one of the few UK homeowners who like the pebbledash aesthetic, why not consider a Silicone Render finish with a 3mm-thick grain size? This way, not only will your house look more aesthetically pleasing in a colour of your choice – that’s right, our Silicone Renders are available in absolutely any colour with our colour-mixing facilities – but, in the thickest grain size available, the Silicone Render will also replicate that pebbly finish. A win-win!

Why should I render over my pebbledash with Silicone Render?

Where do we begin?! Covering your pebbledash with Silicone Render can:

  • Dramatically enhance the aesthetics of your home

The primary reason for applying Silicone Render onto a property is to improve the aesthetics of the property. Silicone Render not only brightens a shabby wall but provides a facelift to the whole property. What’s more, Silicone Renders are highly breathable, so they will help to prevent problems with dampness and mould on your walls, which is especially beneficial in areas that are more exposed to organic matter. And, as well as the 3mm thickness, Silicone Render is available in 0.5mm, 1mm, 1.5mm and 2mm thickness, allowing you to achieve your desired textured finish.

  • Massively improve the thermal performance of the building

If you’re also applying external wall insulation, that is. While applying OCDC followed by a render topcoat alone can provide insulating benefits, you can imagine how many more benefits external wall insulation underneath will provide! Typically, rendering a property costs £50-60 per square metre; external wall insulation with render costs around £100 per square metre. Therefore, if you’re going to invest in render, it’s worth going that extra mile and adding external wall insulation, saving more on energy bills in the long run.

  • Greatly reduce the risk of penetrating damp

Another reason people choose to render their homes is to resolve issues with water ingress and penetrating dampness. Some forms of brick, especially in exposed areas, can be liable to damp if exposed to the elements over a long time. Applying render to the external walls blocks the path of water into the property and prevents dampness from occurring. Nonetheless, if you have cavity walls, this problem shouldn’t be occurring anyway.

Which Silicone Render should I choose to cover my pebbledash?

Here at EWI Store, we offer several types of Silicone Render:

All of these renders are manufactured by EWI Pro who specialise in providing long-lasting render solutions. Each Silicone Renders offers three main characteristics: they are hydrophobic (meaning they repel water), breathable and flexible; they rise in performance and quality from Silicone Silicate Render to Nano Drex Silicone Render.


So, what are you waiting for? If you have a pebbledashed property that is looking old and tired, then it might be time to consider using either OCDC followed by a render topcoat or an external wall insulation system with a render finish. We hope you found this blog useful in learning how to best cover your outdated pebbledash façade! If you have any more questions, do not hesitate to get in touch with our experienced Sales Team who will be happy to help based on their expertise.

EWI Store are the leading UK render specialists, offering a range of high-quality Render and External Wall Insulation products. We take a whole-system approach to external wall insulation, stocking all the materials required to help installers achieve a stand-out result. Our selection of products is constantly growing as we strive to offer our customers the best possible choice of materials from trusted manufacturers and established brand names.

Repointing mortar or External Wall Insulation: Which do I need?

Mortar refers to the substance that ‘glues’ bricks together and helps to protect walls from water ingress and heat loss. It has a long and successful history, with the earliest record from Israel which is thought to date back as far as 10,000 years, and many other examples of age-old mortar still exist today. For instance, if your house was built pre-1930, it’s likely that it was built with lime mortar; alternatively, if your house is a new build, it was probably built with Portland cement. Needless to say, mortar can eventually begin to crack, meaning it needs to be either ‘repointed’ – that is, filled in or repaired – or you should have external wall insulation installed on your home.

Here at EWI Store, we’re often asked lots of questions about mortar, with the most common being “what is mortar made of?”, “is mortar the same as cement?” and “is mortar waterproof?”. In today’s blog, we’re going to answer all these questions by explaining how mortar is made, the main types of mortar and how to tell whether it’s time to repoint your property or have external wall insulation installed.

What is mortar made of?

Mortar is comprised of materials such as cement, sand and water, and sometimes lime, to create a high-quality substance to seal bricks together. It is either mixed on-site using a concrete mixer or manufactured in a factory off-site by expert suppliers.

What’s the difference between lime mortar and Portland cement?

Lime mortar is generally produced by burning calcium-based raw materials; in the UK and Ireland, chalk and limestone are most commonly used. When these materials are heated to about 850oC, the heat removes the carbon dioxide, leaving calcium oxide or ‘quicklime’. The quicklime is then submerged into the water for weeks or months to create a lime putty, or ‘slaked lime’, which is then mixed with sand and water to create the lime mortar.

Portland cement was invented around the 1820s by heating limestone with clay, mixing it to create a slurry, then heating it again. This formula achieved quick drying times, which helped it gain its commercial recognition and become the favoured additive to residential and commercial lime mortars.

Is mortar the same as cement?

Understandably, the name “Portland cement” can cause confusion in that it sounds like… well, cement. However, cement is a binding powder that is never used alone; it is a component of both concrete and mortar, as well as tile grout and thin-set adhesive. Therefore, cement is an element of mortar, so mortar and cement are not synonymous with one another. To break it down even further, here are the differences between cement, concrete and mortar:


  • Binding component of both concrete and mortar
  • Comprises limestone, clay, shells and silica sand
  • Hardens and gains strength when mixed with water


  • Used for building foundations, slabs and masonry
  • Comprises cement, sand and gravel
  • Forms into a flexible mould


  • Substance that ‘glues’ bricks and blocks together
  • Comprises sand, cement, water and sometimes limestone
  • Not used as a sole building material

Is mortar waterproof?

When rain comes into contact with exposed walls, the water can freeze in the bricks and the surrounding mortar which expands the mortar, thereby causing damage. Not only does this freeze-thaw weathering look unappealing but, the longer it’s ignored, the more likely it’ll lead to a cold and damp house. Therefore, if you can see cracks in your mortar, you might want to consider repointing your property.

How much does repointing mortar cost?

Repointing generally costs between £20-£40 per metre squared depending on the condition of the brickwork. In addition, scaffolding may add to the cost. Working out the square meterage of your external walls is easy: you just need to go outside and measure the length and height of the wall, then multiply the two numbers together.

The alternative to repointing mortar: External wall insulation

If you’re considering investing in repointing, it would be extremely worthwhile to go that bit further and consider having external wall insulation installed onto your home. Both external wall insulation and thin-coat renders will provide a weather-tight seal on your external walls, as well as enhance their appearance, increase thermal qualities and reduce energy costs. It might be more expensive but think of all the long-term benefits! If your property is a cavity wall property, learn more about why you should have external wall insulation installed on your cavity walls here.

Is mortar needed in External Wall Insulation?

If your property has uneven substrates and you’re considering having external wall insulation installed, Levelling Mortar is the perfect product for preparing an even substrate before applying an external wall insulation system. Levelling Mortar is a polymer-modified sand and cement mixture which can be used for repairing and filling cavities and walls, making for an easy installation and application of external wall insulation and render. Read more about the stages of an external wall insulation system here.

We hope this blog was useful in clarifying the purpose of mortar, the difference between lime mortar and Portland cement, the permeability of mortar and whether you need to repoint your mortar or go for external wall insulation. If you have any questions, do not hesitate to comment below or ask our lovely Sales Associates!

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    Installing External Wall Insulation

    Want to spruce up the look of your property? Fed up with the temperature fluctuating in your home? Looking for a way to cut those energy bills? Then, look no further than external wall insulation. The EWI Store team are here to answer all your unanswered questions about external wall insulation and render solutions; find our contact details here to get in touch.

    Shop all your external wall insulation needs now!

    Can you apply render in hot weather?

    As we approach the summer months, you might be wondering whether the hotter weather may impede your plans to apply render to your property – and rightly so. If applied in the right conditions, render can drastically improve the aesthetics of your home but, if applied in the wrong conditions, the aesthetic may not appear as you’d hoped. Read on to learn when and how you should apply render to your home.

    In the past, we’ve received several complaints from homeowners regarding how their render has dried; the most common including the appearance of pinholes and drying faster than expected. Issues like these can be the result of the render being applied in too hot weather conditions or direct sunlight as the product has specific temperature margins within which the product will work at its best. The temperature margins tend to be around 5˚C – 25˚C, but each render’s margins may vary, so you should always check your product packaging to determine its specific temperature requirements.

    These issues, then, do not reflect the quality of the products but the fact that they were applied in inadequate conditions. Although pinholes may occur over time, there is normally a reason for their occurrence. For instance, if a render primer has not been applied, especially in warmer weather, the likelihood of pinholes increases. As the basecoat is very dry and porous, it will absorb the moisture from the render very quickly, thereby massively increasing the risk of pinholes. Render primer, however, prevents this from happening by creating a barrier between the render and basecoat.

    Another reason why pinholes might occur is due to the product drying too quickly. And, again, if a render primer has not been applied, this only exacerbates the problem. To avoid this, apply two coats of the render primer; this creates a stronger barrier between the basecoat and the render, further preventing the basecoat from absorbing the moisture.

    Pinholes can affect most types of render – including silicone render, acrylic render and other thin-coat renders – however, switching to a different product based on this risk alone is not the ideal solution. Not only are pinholes a risk in any type of render, but you may not achieve the aesthetic look you were going for because some renders look very different from each other. What’s more, you will be deprived of all the amazing benefits renders have to offer; for example, a silicone render is extremely flexible, breathable and hydrophobic, unlike many other renders.

    Although pinholes are unsightly, they are not the only aesthetic problems that may occur as a result of applying render in poor weather conditions. As the render, naturally, would dry much faster in hotter temperatures and direct sunlight than it would in normal temperatures, this would reduce the amount of time to correctly apply the product; this may lead to an unfinished or uneven texture.

    It takes four men around three hours to apply 200 square meters of render. By not having enough time to apply the render, you may not be able to use the correct technique; this may result in an uneven textured finish which, in turn, can create the appearance of discolouration. The correct way to apply the render is in circular motions rather than in strips; this will help create that smooth, uniform texture that you envisioned your render to appear like.

    The best way to reduce any of the issues mentioned is, of course, to apply the render in the correct temperatures and use the above techniques to help minimise the chances of pinholes occurring.

    If you plan to complete your project in the middle of summer, the key is to get up early and get going! We have many installers who will start the process as bright and early as 5 am – it might not sound ideal, but it will be worth it in the long run. If possible, avoid applying render in the middle of the day as this is when the sun is at its hottest. Another technique – which may seem a little bizarre at first – is to work by avoiding the sun. What we mean by this is to follow the shadows and 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 while staying away from the glaring sun.

    If you are interested in learning the correct process for applying render, you can enquire about attending one of our market-leading training courses or watch our YouTube video ‘Applying Silicone Render In Hot Weather’.

    Don’t let these small risks put you off. 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.

    If you have any questions, our Sales Team will be happy to help! You can find our contact details here.

    Why you should have External Wall Insulation on your Cavity Walls

    Whether your house should occupy cavity wall insulation (CWI) or external wall insulation (EWI) is an age-old question that still leaves homeowners confused. While it seems obvious that CWI should be installed on cavity walls and EWI on solid walls, there are many benefits to having EWI installed on your cavity walls. Of course, the decision ultimately comes down to what best suits both your budget and your property; however, with CWI’s history of creating issues surrounding damp and mould compared to EWI’s aesthetically pleasing and energy-saving properties, it’s clear why EWI is quickly becoming the favoured choice.

    If you’re still torn on which type of insulation would be best for your home, we’ve compiled a little guide on the advantages and disadvantages of both CWI and EWI to aid your decision.

    Advantages of Cavity Wall Insulation

    If CWI is the only option for you, it does offer some benefits:

    • CWI does not alter the external appearance of your property
    • CWI helps to reduce your energy bills
    • CWI keeps your house warmer in the winter
    • CWI helps to reduce your carbon footprint
    • CWI is very quick and easy to install
    • CWI is cheaper than EWI

    Disadvantages of Cavity Wall Insulation

    If you are considering CWI, it is important to consider these factors:

    • CWI is at risk of being improperly installed by underqualified installers
    • CWI has been known to trap moisture and cause dampness when poorly installed
    • CWI restricts the amount of insulation that can be installed (dependent upon the size of the cavity), making it less effective than EWI
    • CWI is not suitable for all buildings (i.e. solid wall structures)

    Advantages of External Wall Insulation

    In contrast, EWI offers many benefits:

    • EWI massively improve the façade of a property due to the decorative topcoat
    • EWI has no restriction as to how much insulation can be installed (you can get up to 200mm+)
    • EWI regulates the thermal comfort of your home, thereby reducing energy costs
    • EWI materials such as Rockwool have soundproofing capabilities as an added advantage
    • EWI has minimal risk of dampness and condensation issues
    • EWI does not cause thermal bridging
    • EWI prolongs the lifespan of the building by protecting its exterior walls
    • EWI increases the value of the property in terms of its energy efficiency and external appearance
    • EWI requires very little maintenance
    • EWI is suitable for virtually any property type

    Disadvantages of External Wall Insulation

    Though not strictly disadvantages, there are some things to consider before installing EWI:

    • EWI is more expensive than CWI due to the number of materials required and the higher level of skill required to install it, but its long-term benefits make it worthwhile
    • EWI requires skill to install to ensure it is safe and won’t cause problems further down the line, so you need to be careful as to who you hire
    • EWI can be difficult to get planning permission for on older properties as it creates a completely new exterior
    • EWI may need the occasional touch up to ensure the render topcoat remains fresh, but this can be easily completed by giving it a little wash and by using our Silicone Paint

    The verdict: Why you should choose External Wall Insulation

    If you already have CWI installed and it’s not as effective as you would like it to be, you can certainly have EWI installed as well. By doing this, not only will you achieve two layers of insulation but any thermal bridges within the existing CWI will be negated by the EWI. Together, CWI and EWI will achieve maximum aesthetic and thermal performance.

    Nonetheless, the downside is that you can’t have one without the other; trying to install EWI onto an empty cavity wall will achieve very little given that the air within the cavity will be heated up before escaping. Therefore, if you don’t have CWI insulation already, be sure to have that installed first, then consider EWI at a later date.

    To conclude, EWI offers an array of benefits to an insulated cavity wall property; it greatly increases the thermal comfort, massively enhances the façade and even prolongs the lifespan of the building, to name a few. If you’re looking for more advice on having EWI installed onto your home, do not hesitate to reach out to our technical team who are available to help every step of the way!

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      How to fix cracked render

      While sand and cement render is still commonplace on many properties throughout the UK, it has one major issue: it is prone to cracking. Traditionally six parts sand and one part lime, sand and cement render is typically applied at a thickness of around 20mm and coated with masonry paint to complete the aesthetic. While lime can enhance flexibility, this render is still not flexible enough to withstand natural movements of a building (namely, expanding in the summer and shrinking in the winter), therefore causing ‘hairline’ cracks. Such cracks can not only impact the overall aesthetic of a property but also lead to water ingress, causing further issues down the line, including dampness, heat loss and mould. If you’ve noticed cracks of any kind on the façade of your property, you’ve come to the right place as we’re going to explain how to fix cracked render.

      If you’ve read our blog comparing sand and cement and thin-coat render systems, you’ll know that thin-coat renders are extremely flexible and therefore far less likely to crack than sand and cement render. As mentioned, sand and cement render is typically applied at a thickness of around 20mm; in contrast, thin-coat renders are exactly that: thin-coat, meaning that they range from 1mm to 3mm in thickness depending on the grain size chosen. What’s more, our thin-coat render systems are comprised of a flexible basecoat, embedded with fibreglass mesh for extra strength and crack resistance, then finished with a thin-coat render for a smooth, aesthetically pleasing finish. Going forward, we highly recommend choosing a thin-coat render system as their flexibility, durability and crack resistance is second to none.

      Depending on the size, severity and stage of development of the crack(s) on your property, there are several options for fixing cracked render.

      cracked render

      1. Fixing completely damaged render

      If the render is damaged all over (namely, full of cracks or peeling away), you have two options:

      • Start again

      The best solution for fixing cracked render is to start again! While this might not be what you wanted to hear, putting any other materials on top of cracked render is akin to using glue: it is only a temporary fix and, over time, the cracks will only continue to expand and worsen. Therefore, we always recommend stripping the existing render back to the brickwork, but we appreciate this may not be an option due to the time and cost implications.

      • Add a thin layer of EPS insulation

      The next best solution is to add a thin layer of EPS insulation (20mm or 30mm) to the wall; this first needs to be attached with adhesive, then anchored using mechanical fixings. Before adding the insulation board, try to remove any very loose render and make good the surface with a Levelling Mortar. Then, once the insulation boards are in place and the adhesive has set, you carry on the rest of the system as normal. On top of the insulation boards, apply a 6mm-thick basecoat layer with embedded reinforcing fibreglass mesh followed by a thin-coat render topcoat to provide a decorative finish. For more information on how much this render system typically costs, be sure to check out this blog on the cost of coloured render per square metre.

      Essentially, applying a thin layer of EPS means that you are creating a new, stable substrate onto which you can apply the thin-coat render system. Also, it means that you will boost the thermal performance of your home, albeit this is relative to the thickness of the layer of insulation.

      2. Fixing cracked render on just one panel

      If only one panel – that is, one side of the house – is cracked, we recommend first filling the crack with our Levelling Mortar, then applying fresh layers of a basecoat and a topcoat render to that one panel. Hopefully, the panel in which the crack has occurred doesn’t comprise the whole side of the house caused naturally by, for instance, a downpipe, which can disguise where the new render meets the old render. The breathability of the basecoat, combined with the flexibility of the render topcoat, should provide a crack-free solution.

      3. Fixing small cracks

      There are some cases where a very small crack has occurred that needs fixing; for example, when a car has ‘gently’ hit the wall. In this situation, you have a couple of options.

      Firstly, you can remove a square of render around the affected area and apply a basecoat and render topcoat to this area. This involves taking an angle grinder and cutting a clean square around the impacted area. The downside to this option, however, is that scarring where the new render meets the old render is inevitable as a consequence of the thinness of the new render. The square, marked out using rendering tape, ensures that the scar looks neat regardless.

      The other solution for fixing a small crack is to apply a basecoat to the whole panel and re-render the property; again, this requires a bit more work, but you won’t be able to see where the original crack in the render was. This provides a nicer finish than marking out the square (as above).

      We often see customers order additional buckets of render to make repairs on cracked or damaged render to simply ‘touch up’ the affected area but, 99% of the time, this will result in unsightly, visible scarring. That’s why we always recommend following one of the methods described in this blog depending on your circumstances.

      Which thin-coat render should I go for?

      Here at EWI Store, we offer four thin-coat coloured renders to choose from:

      • Silicone Render: Silicone Render is a premium, modern coloured render that is available in hundreds of colours. Silicone Render is a very popular choice because it offers hydrophobic properties, meaning that it repels water, dirt and organic growth, thereby requiring very little maintenance. Silicone Render is also extremely easy to apply because it comes ready to use, so you can apply it straight from the pot. Read more about Silicone Render here.
      • Silicone Silicate Render: Silicone Silicate Render is our most popular hybrid-silicone render. Silicone Silicate Render is our best-value render, offering the key benefits of a thin-coat render as well as the breathability, vapour-permeability and self-cleaning properties of silicone. If performance and functionality at a great price point are priorities, Silicone Silicate is a great choice.
      • Acrylic Render: Acrylic Render is very similar to silicone, except it doesn’t provide the same breathability. It’s a solid middle-ground thin-coat render because it still provides the same flexibility and is great at holding onto colour pigment. So, this is also a fantastic choice if you are looking to fix a cracked render. Read more about Acrylic Render here.
      • Mineral Render: Mineral Render is a dry-mix thin-coat render. This is a very popular choice if you live in a cold or rainy climate because mineral render is extremely fast-drying. The only downfall about this render is that you need to paint over it with silicone paint to seal it in because, if it’s left exposed to the elements, it can develop lime bloom due to its inclusion of Portland cement. Read more about Mineral Render here.

      At EWI Store, we are very happy to provide help with cracked render. The best way to resolve this is to send photos to [email protected] so that we can provide bespoke, expert advice on how to best fix the cracked render!

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        Can you paint over K Rend?

        Is your house currently rendered in K Rend? Has it been a while since your house was rendered? Is it looking a bit dull and dirty? If this sounds all too familiar, then it might be time to consider refreshing the façade of your property. Simply painting over the render might sound like the most obvious way to achieve this, but there’s slightly more to it than that. This blog unpacks how to go about painting over a property rendered in K Rend but not before explaining what K Rend is to help you identify the type of render on your property in case you’re not sure.

        What is K Rend?

        Due to its renown, K Rend is often confused as the umbrella term for all types of render when, in fact, it is a brand of render. Here at EWI Store, we stock K Rend Silicone K1 Monocouche Render and K Rend Silicone TC15 Topcoat. K Rend Silicone Render is water-repellent, polymer-modified and self-coloured, meaning it is available in a variety of colours so you can achieve your desired coloured finish.

        How long does K Rend last?

        While K Rend looks fantastic upon application, it can eventually look a bit grubby due to prolonged exposure to the elements. If you can see black, red or green streaks anywhere on the façade, this is a sign of biological growth and an even bigger sign that it simply needs a good clean; a simple jet wash should do the trick. It is vital to get rid of any biological growth before painting over the render as it can continue to grow under the paint, defeating the purpose of refreshing the face of the property. Nonetheless, too high pressurised water can cause damage to the surface of the property, so it is worth considering hiring a professional to clean it for you.

        How can I paint over K Rend?

        Once your property is clear of dirt and biological growth, it can be painted. However, while it is possible to paint over K Rend with standard masonry paint, it is advised to consult with a professional who can recommend more compatible paints as masonry paint can compromise the render system. For instance, our Silicone Paint works with our Silicone Render to offer advanced breathability, flexibility and durability, which can also be tinted to match the very same colour as the current façade or to absolutely any colour you like, including any RAL and NCS colour. If you need assistance, you can contact our experienced technical team here!

        The verdict…

        So, to answer the question at the beginning, you can paint over K Rend. However, some factors need to be considered before doing so, such as the condition of the render before painting (does it need a good clean?) and the type of paint to use over K Rend (which should be discussed with a professional). Once these factors have been considered, your property can be given a lovely refresh! Don’t forget that you can contact our knowledgeable team regarding any other questions you have, or fill in the form below to send your request.

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          Stages of Installing an EWI System

          Stages of installing an EWI system

          You might have heard about external wall insulation (EWI) through the likes of… well, us, or seen it in action whilst it’s being installed on your neighbours’ homes, but what you might not be so familiar with is how it’s installed. Here at EWI Store, we aspire to ensure that all our customers are fully informed about our EWI systems, including how they are installed in certain ways and why, and that what’s this blog is for. Here’s a simple step-by-step guide on how to install an EWI system.

          Wall preparation

          Before any work can begin, the external walls must be prepared. The preparation required varies depending on the condition of the building. In most cases, a simple scrub will do, but sometimes the existing external wall coating needs to be removed entirely. If you are installing EWI onto a smooth surface, then you will need to use our EWI-310 Universal Primer to allow the adhesive to stick to the walls. Alternatively, if the wall surface is uneven, the EWI-260 Levelling Mortar must be used to prepare the wall. To remove any organic growth, consider using a fungicidal wash.

          Starter tracks application

          Once the wall has been prepared, it is time to apply the starter tracks. The types of starter tracks to be applied depend on the EWI system being installed. The correct starter tracks should be applied to the walls above the DPC (damp-proof course). The starter tracks not only allow for the easy installation of insulation to the walls but also protect the surface of the insulation from weather, damp and other damage. The clip-on profile should be attached to aluminium starter tracks to create a neat finish between the starter track and the insulation.

          Insulation application

          After the starter tracks, the basecoat should be applied to the insulation using our modified dot-and-dab method (three dots in the middle and a layer all around the perimeter). For reference, the EWI-220 EPS Basecoat can be used as an adhesive. Use a notched trowel to spread the basecoat evenly across the back of the insulation board. The basecoat should be about 4-5mm thick. When placed on the wall, mechanical fixings should be used to enhance the security of the insulation (6 fixings per square metre of insulation). Allow 2-3 days for the basecoat to set before installing the mechanical fixings.

          Beading and Verge Trims application

          Before adding the basecoat, all beading must be applied. Beading is used to reinforce weak or impact-prone areas within the system, helping to prevent damage and reinforce structural integrity. Each beading has its own special function and area of application:

          • Corner beads: Corner beads are embedded with mesh which sinks into the basecoat. Corner beads reinforce the external corners of the EWI or render-only system.
          • Movement beads: Movement beads are used inside the corners of thermal insulation systems to create a permanent and weather-proof sealant of vertical movement joints.
          • Bellcast beads: Bellcast beads are designed to provide a clean, natural stop to the render just above the DPC. The bellcast bead also propels water from the wall.
          • Render movement beads: Render movement beads should be used where there is an expanse render area. The render movement bead should be applied vertically and is designed to prevent cracking within the render through thermal expansion and compression.

          Basecoat and mesh layer application

          After 2-3 days, another layer of the basecoat should be applied with a notched trowel over the top of the insulation boards at a thickness of 5-6mm. Then, fibreglass mesh is embedded into the basecoat in vertical strips using the flat edge of a notched trowel. Each vertical strip of fibreglass mesh should overlap its neighbouring vertical strip by approximately 10-15cm. At EWI Store, we recommend using fibreglass mesh because it increases the tensile strength of the system and goes an extra step further in preventing cracks and impact damage.

          Render Primer application

          Render primer is classed as an optional step, but to enhance durability and adhesion, we highly recommend applying a render primer to the basecoat. The render primer you use will depend on the render topcoat. For instance, if you’re using our Silicone Silicate render, the Topcoat Render Primer is the most suitable. Alternatively, for our Acrylic render, the Mineral and Acrylic Primer is most ideal. This should be painted on and then left to dry for 12 hours; check out our blog all about our primer range for a deeper insight into render primer and its properties.

          Render application

          Once your final basecoat layer is dry, the final step is to apply the render. When we talk about render, we are referring to our thin-coat render range. The thickness of the render determines how thick the layer should be on the wall. For instance, if you select one of our Silicone Renders with a thickness of 1.5mm, the render should be applied no thicker than 1.5mm from the surface of the wall because, even though our renders are extremely flexible, durable and breathable, this can hinder the EWI system. At EWI Store, our range of advanced silicone renders can be tinted to absolutely any colour, catering to any taste and enhancing the external appearance of your property whilst also improving its thermal comfort.

          And, there you have it! Although this is a very basic installation guide that should be used merely for informative purposes, we hope you found this blog helpful in explaining the stages of installing an EWI system. Every installation is different so, if you have any further questions about installing EWI on your property, do not hesitate to call our technical team who are always happy to assist!

          Can You Paint Over Silicone Render?

          Have you had your Silicone Render for quite some time now? If so, you might be wondering how best to give it a little refresh. Here at EWI Store, we’re often asked how Silicone Render can be maintained to continue to exude a stand-out finish. Although Silicone Render has advanced self-cleaning properties, that doesn’t mean that it’s not completely susceptible to gathering dirt over time. To solve such, a gentle clean with a jet wash is perfect now and then however, houses that are likely to become dirty more easily – that is, those on busy roads or in highly-vegetated areas – may need to be painted over. That said, you might be wondering whether you can use standard masonry paint on top of Silicone Render. The simple answer is, while no one can stop you from doing so, it is highly recommended to use Silicone Paint instead. Keep reading to find out why.

          Why use Silicone Paint on top of Silicone Render?

          Silicone Render is a specialist, breathable render product ideal for application on external wall insulation systems where a breathable insulant, such as Mineral Wool, is being used. Therefore, while you technically can use standard masonry paint on top of Silicone Render, we recommend that you use Silicone Paint because it is also highly breathable. A standard masonry paint might not have such breathable properties which would completely nullify the render system’s ability to allow water vapour to pass through its surface, while a breathable Silicone Paint would work with the Silicone Render to continue to offer optimum performance.

          The best thing about our Silicone Paint is that it is available in thousands of colours. If your current render system is coloured and you’re afraid that you won’t find a colour to match, never fear – our Silicone Paints can be tinted to absolutely any shade! That way, not only will the Silicone Paint still cater to your taste, but it will also freshen up the entire façade of the property and extend its lifespan.

          How to apply Silicone Paint onto Silicone Render

          Before you apply Silicone Paint to your render, there are a few preparatory steps that must be taken to ensure a flawless finish. First, you’ll need to clear the render of any dirt or grime. If the walls have been painted previously, you’ll need to remove any flaking paint using either a jet washer or a wire brush. Also, be sure to apply tape to areas that need protection from the paint, such as window and door frames.

          Silicone Render is incredibly flexible and therefore highly unlikely to crack. However, if you notice any minor cracks, these too need to be filled.

          We recommend applying the paint using a standard brush and roller, starting at the top and working your way downwards to catch the paint as it drips and runs. Silicone Paint can be applied in multiple coats, so once the first is dry (after about 12 hours), you can go over it with as many coats as desired. However, beware that – if your render has a finer grain size – the more coats of Silicone Paint you apply, the less visible the grain size will become.

          So, if you’re looking to paint over your Silicone Render, look no further than Silicone Paint. Silicone Paint is the perfect solution for allowing your render system to continue to offer optimum performance, refresh the façade of your property and extend the façade’s lifespan. If you’re looking for a complete guide on how to maintain your render finish, be sure to check out our blog on how to look after your render finish here. As usual, if you have any questions, do not hesitate to contact us or comment below!


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            Receive a FREE Render Colour Chart (and beanie)!

            As a thank you to all our loyal customers and advanced installers, we at EWI Store are offering FREE Render Colour Charts AND EWI Pro Beanies! Our Render Colour Chart is a fantastic resource for customers and installers alike, so you don’t want to miss out on this opportunity. If you’re wondering what a Render Colour Chart is, or equally how to receive your free copy, keep on reading!

            What are Render Colour Charts?

            At EWI Store, we understand that choosing the right render colour for your property can be a difficult decision; it’s hard to visualise exactly how the colour you want – or think you want – will look on the finished facade. And, when you hear that we offer thousands (yes, thousands) of colour choices, you can feel even more overwhelmed. That’s where our Render Colour Charts come to save the day!

            Our ability to tint our render to absolutely any colour, including any RAL, NCS or Pantone shade, means that we cater to absolutely every taste. Our Render Colour Chart is available for our entire thin-coat render range, allowing you to visualise realistic colours and textures before making your final decision.

            Our Render Colour Chart is not just a leaflet with small images; it is a durable, compact hardback brochure that provides official swatches of different render colours and grain sizes. Our installers find them to be an extremely handy resource, so you don’t want to miss out on receiving one for FREE!

            How can I receive my free Render Colour Chart?

            If you are not already registered with us, you will first need to create a trade account with us. Click here to register your account with us. If you are already registered with us, simply make sure you are logged in to your account.

            Then, to receive your free Render Colour Chart, simply go to your cart and enter the code colourchart21 in the text box. What’s more, you will also receive a free EWI Pro Beanie AND free postage with your free Render Colour Chart – what a deal!

            On behalf of everyone at EWI Store, we want to thank you for your custom and loyalty. We hope you enjoy your free gifts!

            Coloured Render Cost Per Square Metre

            Here at EWI Store, we offer a vast range of coloured renders to both improve the look of your home and cater to every taste. Our renders can be tinted or matched to absolutely any colour, including any NCS, RAL and Pantone colour, allowing for maximum colour customisation. What’s more, with their advanced breathable, flexible and self-cleaning properties, rest assured our renders will offer your property the utmost protection.

            Choosing a coloured render for your property can be overwhelming. That’s why we offer colour charts and render tester pots to assist you in deciding which colour is best for you before making a purchase. However, once you’ve made the all-important decision as to which colour you’d like, you’re probably wondering: how much will it cost? Well, wonder no more, as we’re here to help!

            Calculating the cost of coloured render per square metre

            To work out exactly how much coloured render you will need for your property, we first need to work out the approximate square meterage of the property.

            Working out the square meterage of your external walls is easy: you just need to go outside and measure the length and height of the wall, then multiply the two numbers together. This needs to be repeated for each wall you intend to render, then totalled all together; this total will give you the external wall area.

            Priming the substrate

            Assuming the substrate is standard masonry, we recommend that you use our Water Based Primer, which costs around 30p per square metre.

            Applying the Basecoat and Mesh

            Then, we need to take into account the basecoat layer, which goes on before the coloured render to smooth out the external wall and aid adhesion. Fibreglass Mesh is also embedded in the basecoat. One bag of our EPS Basecoat will cover 4 to 5m2, which will cost £2.40 per m2. The Fibreglass Mesh, which will be embedded within the basecoat, will cost approximately 70p per square metre.

            Using a Render Primer

            Now, we need to consider how much render primer your property will require. For a Silicone Silicate system, you’ll need our EWI-333 SiSi Render Primer, which can also be tinted to match the colour of the render for extra opacity and pigmentation.

            A large 21kg bucket of Render Primer will cover approximately 60m2. This means that the primer will come to roughly 80p per square metre.

            • Top Coat Primer – 20kg

              £67.00 (incl VAT)

            Choosing a render

            Let’s assume you want to go for a Silicone Silicate Render. First, we need to calculate how much Silicone Silicate Render costs per square metre.

            For instance, one bucket of Silicone Silicate Render – with a grain size of 1.5mm – will cover between 9 and 10m2, which is roughly £4.90 per square metre.

            When buying your render, remember that coverage will vary based on the grain size that you go for; the larger the grain size, the more product you will need because it will provide less area coverage.

            Silicone coloured render

            Beading per m2

            Finally, we find that beading usually costs approximately £2 per square metre, although this can vary depending on the property.

            The total cost of Silicone Silicate coloured render system per square metre

            Altogether, the cost of a Silicone Silicate Render system per square metre approximately come to £10.80. Bear in mind that this is an approximation. Nonetheless, if you were to multiply this number with the square meterage of your property, you should get an idea as to how much the materials will cost for installing coloured render on your home!

            Which coloured render do I choose?

            We have a huge range of coloured renders to choose from, all of which are BBA-approved and of the highest quality on the market.

            We also provide tester pots that allow you to test different colours. It’s always best to see the coloured render in-person to ensure that you are happy with your decision before it’s applied all over your property.

            Our thin-coat-coloured renders are bestsellers. We offer:

            • Silicone Render/Silicone Silicate Render: Silicone Render is a premium, modern-technology coloured render which is available in hundreds of different colours. It is a customer favourite as it offers hydrophobic properties, meaning that it repels water, dirt and organic growth. Silicone Render is also ready-to-use, making it super easy to apply; it can be applied straight out of the box! Read more about Silicone Render here.
            • Acrylic Render: Acrylic Render is very similar to Silicone Render, except it doesn’t provide the same hydrophobic properties. Saying that, it still provides the same flexibility as other thin-coat renders and is great at holding onto the colour pigment; it’s a solid middle-ground thin-coat render. Read more about Acrylic Render here.
            • Mineral Render: Mineral Render is a dry-mix, thin coat render. This is a very popular choice if you live in a cold or rainy climate because mineral render is extremely fast-drying (you can’t apply other renders in cold or wet conditions as they take longer to dry). However, this render needs to be painted afterwards with silicone paint to seal it in because, if it’s left exposed to the elements, it can develop lime bloom due to its inclusion of Portland cement. Read more about Mineral Render here.
            • Monocouche Scratch Render: Monocouche Scratch Render is a thick-coat, through-coloured render. It is more traditional but does require extra work to install; it needs to be applied in two passes to provide extra strength and cannot be applied in wet or humid conditions. Monocouche Render also needs Fibreglass Mesh embedded within it to provide extra strength and flexibility, ultimately making it crack-resistant. Then, once it’s dried, it needs to be scratched back to achieve the desired texture. If our monocouche system is of interest to you, check out our blog Monocouche Scratch Render Cost Per Square Metre for a detailed insight into how much you’re looking at with this system.

            How much does Coloured Render cost to maintain?

            Let’s say, 10 years down the line, you want to give your render a bit of a refresh; Silicone Paint is a great way to do this as it can be matched to the exact colour of your existing render. To learn more about why Silicone Paint is best for refreshing an existing polymer-modified render, you can read this blog. However, in terms of sprucing up your render, a 15l bucket of Silicone Paint typically covers 60 to 70m2. Therefore, you’re looking at around £3 per m2.

            So, what do you think? Does Coloured Render sound right for you? Was this blog helpful? Be sure to comment with your thoughts and questions, should you have any, below – again, we’re here to help!



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              Applying Render to Cement Board

              What are cement boards?

              Cement boards, also known as “render carrier boards” or “weather carrying boards”, are sheets comprised of cement and reinforcing fibres used as tile backing boards as a base for render and external wall insulation. Combined with magnesium, an oxide coating and fibreglass mesh, cement boards create a solid surface that can withstand extreme weathering, including rain, wind and snow. What’s more, cement boards do not rot or swell when they encounter water, meaning they can stand the test of time even on the exterior of a property. The most common cement boards on the market for render are Aquapanels, Renderflex and Siniat boards.

              Applying render to cement boards

              Cement boards can be finished in numerous ways however, one of the most effective ways is to apply render. Not only does render enhance the external appearance of a property, but it improves its thermal performance and thereby reduces energy costs. With that, let us explain how to apply render to cement boards!

              Step one: Priming the cement boards

              The first step to applying render to cement boards is to prime the boards. We recommend using our EWI-310 Universal Primer as the presence of silicate in the render creates an excellent adhesive for the basecoat of the render (to learn more about how primers work, make sure to check our complete guide to EWI Primers). The Universal Primer comes in 20kg buckets, and each bucket can cover between 60 and 80m2 depending on the absorption from the cement board. The primer should be applied to the cement board using a brush or roller; its red colour allows you to see clearly where on the wall it has been applied. For best results, allow the primer to dry completely before applying the next layer.

              Step two: Applying the basecoat

              After the primer, applying the basecoat to the cement board is relatively easy. Firstly, an adhesive must be applied; our adhesives come dry, meaning they must be mixed with water before application. We recommend using either EWI-220 Basecoat Adhesive or EWI-225 Premium Adhesive depending on how solid you would like the facade. Upon being mixed with water to form a grey putty, the adhesive should be applied with a notched trowel. For best results, use a 10mm-sized notched trowel for applying a 6mm-thick layer of adhesive to the cement board.

              Once the adhesive has been applied, the fibreglass mesh can be embedded within the adhesive; it is this mesh that makes our render systems so flexible. The fibreglass mesh comes in rolls which must be applied vertically, overlapping one another by 10cm, within the adhesive; this can be achieved by drawing the flat edge of the notched trowel up from the bottom of a wall to pull the adhesive through the holes of the mesh. Our EWI-66645 Orange Fibreglass Mesh rolls are 50cm in length, 1m in width and cover 50m2.

              As the render topcoat is so thin, it is vital to ensure that the basecoat is completely smooth. If the basecoat is still not completely smooth even after the mesh has been embedded, the easiest solution is to produce a very wet adhesive mix to apply to the basecoat.

              Step three: Priming the basecoat

              Once the fibreglass mesh-embedded adhesive is completely smooth, the wall needs to be primed ready for the render. The primer used depends on the type of render however, provided you match the primer with the render, the principle is the same. For example, our EWI-333 Silicone Silicate Primer comes in either 7kg or 2kg buckets and can be applied using a paintbrush or roller, with the 7kg bucket covering approximately 20m2 of the wall and the 2kg bucket 70m2.

              • Top Coat Primer – 20kg

                £67.00 (incl VAT)

              Step four: Applying the render

              As soon as the basecoat primer is dry, it is time to apply the render!

              The majority of EWI Pro renders are thin-coat renders, so the thickness of the topcoat is determined by the grain size of the render. For instance, our EWI-040 Silicone Silicate Render comes in four different grain sizes – 1mm, 1.5mm, 2mm and 3mm – so, if you are to purchase a 2mm-thick Silicone Silicate Render, the topcoat should be applied no thicker than 2mm thick. We have received various reports of the render being applied too thick and thereby impinging on the desired finish, so it’s vital to remember that the thickness of the render itself and render facade must match!

              With that in mind, make sure to apply the render to the cement board with a trowel as you can pull off any excess with the trowel, too. Once any excess has been removed, leave the render for five minutes, then work the render in a circular motion using a plastic float to achieve the desired finish.

              And that’s how render is applied to cement boards! If thin-coat render systems are of interest to you, make sure to check out our blog on coloured render costs per square metre for an accurate idea as to how much the materials for such a system typically cost. If you have any questions, do not hesitate to comment below or contact us!


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                The Best Masonry Paint? Silicone Paint

                Are you interested in re-rendering your property and seeking high-quality masonry paint to coat the render for a fresh, modern finish? Then look no further than Silicone Paint! At EWI Store, we often receive enquiries about our Silicone Paint, the most common being “what is Silicone Paint?”, “what is Silicone Paint used for?” and “what’s the difference between Silicone Paint and Silicone Render?”. If you’re wondering the same, don’t worry – we’re going to cover everything you need to know about Silicone Paint right here, right now!

                What is Silicone Paint?

                Silicone Paint is a high-performance masonry paint that can be used for painting over either an existing Silicone Render to refresh the facade, or over our Mineral Render to seal the render. It is highly breathable, waterproof and resistant to environmental pollutants, making it perfect for homes in busy or humid environments where render alone may be susceptible to organic overgrowth. Silicone Paint is also available in thousands of colours, catering to every taste!

                What is the difference between Silicone Paint and Silicone Render?

                The names are self-explanatory; Silicone Paint is a masonry paint topcoat, while Silicone Render is a type of render finish. Their only similarity is that they both contain Silicone which provides numerous benefits, but we’ll come to those a bit later!

                While our thin-coat renders come in various grain sizes, ranging from 1mm to 3mm, our Silicone Paint is completely smooth, meaning it can be applied on top of an existing render without disrupting its texture.

                As with our Silicone Paint, our Silicone Render is hydrophobic, meaning it repels water, dirt and organic growth. However, even with all these capabilities, render can eventually look tired after so many years. That’s where Silicone Paint comes in; not only does it offer the render a decorative refresh, but also an extra layer of protection with its same hydrophobic properties, prolonging the render’s lifespan.


                Why use Silicone Paint?

                As we know, the ingress of water is detrimental to external wall insulation and render-only systems. In external wall insulation, the presence of water can reduce the system’s thermal capabilities and lead to freeze-thaw damage. In a render-only system, it can dampen the internal walls, especially in solid wall properties, damaging the overall render. Therefore, as part of external wall insulation or render-only systems, Silicone Paint is particularly beneficial; its breathability allows water to escape through the surface of the paint. Also, its vapour permeability makes it frostproof, meaning it won’t damage the surface of the paint.

                At EWI Store, we always suggest to our customers that our Mineral Render should be sealed with high-performance masonry paint like Silicone Paint. Mineral Render is our fastest-drying render, making it perfect for cold climates. However, its ingredients mean that, if exposed to the elements for too long, it can be susceptible to lime bloom. That’s why Silicone Paint is necessary as a topcoat; it prevents water from travelling through to the render and forming lime bloom.

                Silicone Paint can be matched to the Silicone Render underneath!

                If you’ve used one of our coloured Silicone Renders, then you can buy a Silicone Paint in the same colour to match! Here at EWI Store, we offer a same-day colour mixing service using our Render Colour Machine, which can tint Silicone Paint to thousands of colours. So, even if your render is not from EWI Pro, we can still match the colour to give it a refresh!


                As well as exteriors, Silicone Paint is great for interiors!

                Up to now, we’ve talked a lot about Silicone Paint can be used as a masonry paint as a render top coat to offer both a protective and decorative finish. However, as for exteriors, Silicone Paint is also great for interiors!

                Given that it’s waterproof, we’ve encountered many people who have used Silicone Paint in their bathrooms, making it perfect for combatting condensation on bathroom walls. Likewise, we’ve heard that people who have previously suffered from damp problems in their homes have used Silicone Paint as a deterrent, limiting the chances of such issues in future. One of our team members has even used Silicone Paint on his garden wall to prevent organic growth! In our opinion, all the above are great ways to utilise Silicone Paint.

                Get in touch to buy Silicone Paint!

                We’re always happy to answer any questions about our products. If you’re interested in using Silicone Paint for your home, don’t hesitate to give us a call so we can discuss its suitability for your situation; we can work out exactly how much you’ll need depending on the square meterage of your property.


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                  Sand and Cement, Monocouche and Silicone Render: Which is best?

                  Of the 28 million properties in the UK, a large proportion are rendered, or at least coated, with some form of protection like pebbledash. However, while pebbledash was vastly popular pre-1930, this aesthetic is now largely considered outdated, making render the go-to for creating a clean, modern look. In this blog, we investigate why render is so popular and the best products to create an incredible finish on your property or home.


                  Originally, UK properties were built with either brick or block. Over time, however, the mortar fusing the bricks together would break down due to natural weathering. Replacing the damaged mortar – known as re-pointing – is incredibly time consuming and, as such, very expensive. Therefore, a feasible alternative to re-pointing a property is to apply render. Render acts as a protective layer for a property; not only does it disguise the existing damaged mortar, but it provides a new facade for the brickwork, offering a clean, modern finish.


                  Traditionally, sand and cement render – typically six parts sand, one part cement and one part lime – was applied to the surface of a property. This render would be applied at a thickness of about 20mm and be coated with paint to complete the aesthetic. As with mortar however, the issue with these traditional renders was that, over time, they would crack due to the natural movements of the buildings by season, expanding in the summer months and shrinking in the winter months. While the addition of lime was intended to provide flexibility to adapt to such movements, the render was still not flexible enough to withstand these movements, causing hairline cracks. Such cracks cause further issues as they would provide an entry point for water to travel behind the render system and, as such, cause it to come away from the wall.


                  In the 90s, several manufacturers introduced a render known as “monocouche”, French meaning “one coat”. Monocouche render is easier to use than sand and cement render as it is premixed, typically four parts sand and one part cement with various other additives; all you need to do is add water. It is applied at a similar thickness to sand and cement render however, once applied, it is scraped to provide a chalkier finish. Monocouche render always uses white Portland cement as the binder; the white base allows for the manufacturer to add a coloured pigment to the render, meaning it does not require paint on top. As such, monocouche became increasingly popular in the 2000s, becoming the go-to product for those looking to render their properties.


                  Again, monocouche render ultimately comes with its downfalls. Firstly, as with sand and cement render, the thickness of monocouche render means that it cannot withstand the seasonal structural movements of the building, therefore causing cracks which again create an entry point for water. Secondly, while monocouche looks fantastic on application, it becomes a hot bed for algae growth as it encounters water. The biological growth on the monocouche can quickly lead to discolouring so, while it initially looks great, it quickly starts to look messy and requires a lick of paint to keep it looking fresh.

                  Then, in early 2000 came silicone renders – sometimes referred to as thin-coat renders – from Eastern Europe. Silicone render fundamentally differed from sand and cement render and ultimately replaced monocouche render. As opposed to a 20mm-thick render, the silicone render maxed out at 7mm and consisted of two main layers: a 4-6mm cementitious basecoat with embedded fibreglass mesh, and a silicone render topcoat typically at 1.5mm thick, although 0.5mm, 1mm, 2mm and 3mm grain sizes are also available. The fibreglass mesh in the basecoat is vital; it provides the render system the ability to flex with and absorb a building’s natural movements, making it crack-resistant – the defining factor and main benefit of silicone render.


                  Much like paint, silicone renders can also be tinted to any colour, providing infinite design options to apply to your property or home. Monocouche renders do come in various colours however, since pigments need to be added in the factory, they are very limited. So, if you need to match a specific colour – for instance, RAL-7016 anthracite grey – then silicone render is the obvious choice as it can quickly be tinted to match the required colour.


                  What’s more, silicone renders are hydrophobic, meaning that they possess self-cleaning properties which repel water. This means that, whenever it rains, the rain carries away any dirt particles from the render system, so the facade stays cleaner for longer. The EWI Pro Premium Bio Silicone render also has added slow-release biocides within the render, helping to prevent biological growth, which is especially useful if the render is being applied in areas of high vegetation.


                  Finally, unlike sand and cement and monocouche renders, silicone renders are lightweight, meaning that they are ideal to use in conjunction with external wall insulation systems. The weight of sand and cement and monocouche renders can pull the face of the insulation away and are therefore not recommended to be applied on top of insulation materials.


                  As this blog has established, render technology has changed significantly over the last 30 years. Whether you have a property that has existing damaged render that needs an upgrade, or even a new build like an ICF or a timeframe building on which you desire an advanced render system, then look no further than silicone render. With a silicone render system, you can rest assured that the facade will not crack over time and will likely stay much cleaner than either sand and cement or monocouche render, therefore providing a render system that will last for years to come.

                  Replacing Pebbledash with Coloured Render

                  Pebbledash is perceived by many as an outdated look for a property; it was frequently used during the post-WW1 housing crisis as a means of covering up quickly-built, slap-dash properties. If you live in the UK, you are most likely to have come across a pebbledash building and, while it’s a durable building method, it’s definitely an acquired taste.

                  What is pebbledash?

                  The pebbledash effect is created by applying a layer of mortar (usually sand and cement) to an external wall and literally throwing pebbles at the wall. Pebbledash houses are still dotted all over towns and cities in the UK and can often have a somewhat dilapidated look. Over time, the pebbles can drop from the wall, leaving the mortar exposed to the weather and therefore vulnerable to absorbing water and causing damp issues. Also, due to its unpopularity, pebbledash can reduce the value of a property purely for its lack of aesthetic appeal. This is why coloured render is vastly more popular because it’s much nicer to look at. Our coloured renders can be customised to absolutely any colour of your choice and can be ordered online or over the phone!

                  How can I replace pebbledash with a coloured render?

                  While we’re not hating on pebbledash (much), you might want to consider re-rendering your property, whether you’re moving into a new home, updating the look of your current property or both. However, as one of our frequently asked questions here at EWI Store, we recognise that there is a knowledge gap on how to apply render on top of pebbledash. That’s why we’ve made this blog – to tackle the question for all you pebbledash homeowners!

                  The short answer is that, unfortunately, you cannot replace pebbledash with coloured render by applying coloured render directly on top of the pebbledash. Saying that, there are several ways around it that you may wish to consider.

                  Essentially, there are three possible options for removing pebbledash:

                  Option 1: Removing the pebbledash

                  The first option is to attempt to remove the pebbledash by hacking it off. However, the main downfalls to this option are that the brick underneath is at risk of being damaged, and there is no guarantee that you will achieve a smooth finish. If this is the best or only option for you, be very careful about who you hire to tackle the task; make sure they are experienced in removing pebbledash. If your pebbledash is forcibly removed, this can really damage the underlying wall and invalidate your house insurance. It’s also important to note that, even after all this, you still wouldn’t be free to apply coloured render directly on the wall. Building regulations stipulate that if you strip it right back to the original brick, then you’ll need to insulate before rendering with a coloured render.

                  Option 2: One Coat Dash Cover (OCDC) to cover up pebbledash

                  The second option is to use the One Dash Coat Cover (OCDC) to completely smooth over and cover up the pebbledash to achieve a clean slate. This product is specifically designed to be applied on top of pebbledash, and it can then be painted or rendered to achieve a modern appearance. The good thing about the OCDC is that it is breathable, so it will allow any trapped moisture within the underlying pebbledash to escape. It can also be applied up to 20mm in one pass (up to a maximum of 50mm), so it’s guaranteed to smooth over the pebbledash nicely!

                  Option 3: Insulate then render over pebbledash

                  A beneficial way of ridding the pebbledash look is by installing 20mm (or thicker, but the thicker you go, the more expensive) external wall insulation (EWI) boards over the top of your pebbledash. This is a great option because the EWI will give you added insulation, which can save you money on bills in the long run.

                  By installing EWI boards, you will also save time and money because hacking off the pebbledash won’t be necessary. Instead, you can simply secure insulation boards over the top of the pebbledash using adhesive and mechanical fixings. Once you have done this, you can apply the render of your choice on top of the insulation boards and achieve a far more pleasing outcome.

                  Which coloured render can I use to replace my pebbledash?

                  There are so many options for replacing your pebbledash with coloured render that it can be quite overwhelming. We want to give you a clear idea of what each coloured render can offer so that you can make the right choice to suit the needs of your property and your personal taste.

                  Thin Coat Coloured Renders to Replace Pebbledash

                  Thin coat renders are a great option for when removing your pebbledash and replacing it with coloured render. Because they are thin-coat, they offer a level of flexibility that ensures that your coloured render finish stays crack-proof for years to come. Thin coat coloured renders are also highly breathable, so they will help to prevent problems with damp and mould on your walls.

                  They also come in different grain sizes, which determines the textural finish that the coloured render will offer you – the bigger the grain size, the more textured the finish that you’ll achieve. If you have simply removed your pebbledash, then you may want to go for a larger grain size as this makes any imperfections in the basecoat less noticeable. Read our blog Coloured Render Cost Per M2 for an idea of pricing!

                  There are three options that you can choose for thin coat coloured renders:

                  • Silicone render/Silicone Silicate render: Silicone Coloured Render is a premium, modern technology coloured render – which is available in hundreds of different colours. Silicone is a very popular choice because it offers hydrophobic properties – which means that it repels water, dirt and organic growth – so it probably requires about the same maintenance as pebbledash (very little). Silicone render is also super easy to apply because it comes ready to use, so you just apply it straight out the pot. (Read more about Silicone Render here).


                  • Acrylic render: Acrylic Coloured render is very similar to silicone, except that it doesn’t provide the same hydrophobic properties. It’s a solid middle-ground thin coat render because it still provides the same flexibility, but it’s also great at holding onto colour pigment. This is a fantastic choice if you are looking to replace pebbledash with a coloured render. (Read more about Acrylic Render here).


                  • Mineral render: Mineral Coloured render is a dry-mix, thin coat render. This is a very popular choice if you live in a cold or rainy climate (as many pebbledash homeowners do – Scotland, coastal homes!) because mineral render is extremely fast drying; you can’t apply other renders in cold/rainy temperatures because they take longer to dry. The only thing about this render is that you need to paint it afterwards with silicone paint to seal it in. This is because, if it’s left exposed to the elements, it can develop lime bloom due to the presence of Portland cement. (Read more about Mineral Render here)

                  Thick Coat Coloured Renders to Replace Pebbledash

                  Thick coat renders are far more traditional but, as the name suggests, they do lack flexibility and breathability because they are applied in a much thicker layer. Once you’ve removed your pebbledash, you can use our Monocouche Scratch Render. Note: thick coat renders aren’t suitable for application on top of insulation boards.

                  • Monocouche scratch render: Monocouche scratch render is a thick coat, through-coloured render. It is more traditional, but does require extra work to install it. This is because the Monocouche needs to be applied in two passes for extra strength and cannot be applied in wet or humid conditions. Monocouche render then needs fibreglass mesh embedded within it to provide extra strength and flexibility (which means it will resist cracking) and then, once dried, it needs scratching back to achieve the desired texture. Read our blog Monocouche Scratch Render Cost Per M2 for an idea of pricing!

                  To conclude…

                  If you are a pebbledash homeowner, looking to re-render, or potentially even install EWI, then we have everything you will need. Check out our materials calculator or get in touch with us directly and we can point you in the direction of one of our fantastic approved installers!

                  Are you a fan of Pebbledash? Leave a comment below…

                  Let’s debate: pebbledash or no pebbledash? Leave a comment below with your opinion; is pebbledash outdated and ugly, or is it a relic from our past that we should preserve for traditional purposes? For those in favour of the pebbledash look, we might have something just for you.


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                    Your Name*

                    Your Email*

                    Your Number*

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