Tag Archives: EWI

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 4-5cm 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!

Monocouche Render vs. Silicone Renders

As you might have noticed, we offer a variety of advanced render systems here at EWI Store, the most popular being monocouche and silicone. Both monocouche and silicone render provide a decorative finish on the external walls of a property whilst also improving its thermal comfort. The result of the external appearance, however, greatly depends on the type of render chosen. In this blog, we discuss the main differences between monocouche and silicone render so that, if you are torn as to which one to choose for your renovation, we can assist in the decision-making process!

Monocouche Render

There are a wide variety of monocouche renders available on the market; here at EWI Store, we stock EWI Pro, K-Rend and Enewall. The key characteristic of monocouche render is that it is a through-coloured, thick-coat render. Monocouche render is very often compared to sand and cement render because it contains cement however, it is very different in terms of texture and characteristics.

Monocouche render tends to offer a chalkier finish than other renders. To provide the finished facade, the render is usually scraped to create a pitted effect. Available in a range of colours (natural and bright), it’s a very popular choice for homeowners who are looking to create a chalky, flat finish.

Silicone Render

Silicone render is a highly flexible, breathable and durable render that comes ready to use in 25kg buckets. Unlike monocouche render, silicone render is a thin-coat render, meaning it is applied very thinly on top of a reinforced basecoat. Although readily available in a standard white, silicone render can be tinted to absolutely any shade. Here at EWI Store, we have specialist tinting equipment that enables us to match to any RAL, NCS or Pantone colour, meaning we can cater to absolutely any taste. Silicone render can be used as a standalone system straight onto brick or applied onto external wall insulation boards to provide a decorative finish.

One of the main advantages of silicone render is that it is crack-resistant. The silicone properties within the render, coupled with the way it is applied, means that it is far less likely to crack than monocouche render.

Now that you know the difference between monocouche and silicone render, you might be wondering how much each cost to install. If so, we’ve got you covered: check out our blogs on monocouche scratch render cost per square metre here and coloured render cost per square metre here to get an idea as to how much you’re looking at.

We offer a variety of advanced silicone-based renders, including Nano Drex Silicone Render, Premium Bio Silicone Render, Silicone Render and Silicone Silicate Render. If you’re interested in trying any of these, be sure to give us a call and our lovely Sales Representatives will be happy to help!

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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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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FREE COLOUR CHART

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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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. Check out our blog Pebbledashing: Dash Receiver or Cement Mix?

We upload a new blog post every Tuesday, so stay tuned for more EWI installation advice, tips for homeowners and product information!

 

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