Monthly Archives: October 2018

cracked render

Why does render crack?

Typically, render is used to provide the building fabric with protection against the elements while also providing an aesthetically pleasing finish. Often, a render is applied to cover up the use of cheaper building materials such as blockwork rather than brick and stonework.

Unfortunately, a common stereotype of render is that it is liable to experience cracking. This is a huge concern for many of our customers, who want to invest in a new render facade but don’t want to find that a few years (or even months) down the line their investment isn’t holding true to its promise.

Cracks are the effect of a number of underlying problems, and if left to their own devices they can escalate a situation from bad to worse by drawing water through the building. There are a number of reasons that render may crack, and in this blog post we’re going to be looking into these reasons.

Weathering

First thing’s first, is your render really old? Render does in fact have a lifespan, especially sand and cement render. If you are living in a fairly old property that is rendered in sand and cement, cracking is going to be inevitable due to the effect of weathering.

When driving rain, snow, frost and more are constantly attacking the exterior of your building, it’s likely that you will experience some kind of negative impact. This is particularly true for sand and cement render, which is incredibly solid, unforgiving and prone to absorbing water. So, consider how old the property is and when it is likely that it was rendered – the age of the render may be the reason for the wear and tear.

Incorrect materials for the substrate

We’ve previously written about a case study where sand and cement render was applied to high performance blockwork, and the resulting finish was a cracked mess within weeks. The reason for the cracked render is that high performance blockwork (this includes Ziegel blocks, AAC, Thermalite etc.) tends to be very soft and malleable, while sand and cement is incredibly solid.

The phrase ‘opposites attract’ just isn’t true in the case of renders and substrates; when choosing a render for your property, it’s imperative that it compliments the substrate so that they will work in tandem. This could be the reason your render is cracking. An installer should be able to advise you on the best type of render for the building fabric.  

Poor quality of workmanship – poor sealing at junctures, incorrect movement joints

A good quality installation from a knowledgeable installer can make all the difference to the durability of your installation. A trusted installer will ensure that correct reinforcement is applied around the weaker areas of a structure, especially around movement joints and reveals.

The render needs to be able to replicate and compensate for movements within the underlying substrate, otherwise it will crack. If this has not been taken into consideration then this could be the cause of the cracks.  

The render dried out too fast

Most common with dry-mix renders, if the water evaporates from the material too quickly it doesn’t leave enough time for the render to bond properly and the surface colour can appear patchy and discoloured.

A render that has dried out too fast is a dehydrated, weak surface and cracking is therefore inevitable. To avoid this, the render needs to be applied in moderate temperatures and if possible away from the direct glare of the sun, and for dry-mix renders if the mixture appears to be drying too fast simply sprinkle it with water as needed.

Fibreglass mesh wasn’t used

Best practice for rendering is to embed fibreglass mesh within the basecoat layer. The mesh is applied in strips that are each overlapped, reinforcing the entire surface of the basecoat and increasing its tensile strength. The result of this is that any movements within the building fabric will be absorbed by the mesh.

If Fibreglass Mesh isn’t embedded within the basecoat or even in the first pass of render, unfortunately this could be a contributing factor towards the cracking.

Structural problems

Sometimes it’s not actually the fault of the render, it’s the effect of underlying structural problems that are making themselves known by damaging the render finish. The structural problems can be numerous and difficult to pin down, whether it’s differential movement between an extension and the main house or due to water and rust.

Rising damp

Rising damp is the fear of all property owners as it’s often difficult to catch and identify. It’s relatively rare, but rising damp is essentially when water travels from the ground up through the walls by capillary action, causing bulging in the walls and floor boards and general structural damage. The structural damage that rising damp can cause is what encourages cracks to form in the external render. You will most likely notice signs of rising damp not just in your render but internally as well, so if this is the case then it needs to be identified and rectified immediately.

Leave a comment down below if you’ve experienced cracking in your render and how you fixed the problem!

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brick slips insulation board

How to use Brick Slips on Insulation Board

Brick slips are an incredibly versatile material, allowing users to realistically recreate a brick effect after applying insulation board to the building. Some people want the benefits of the external wall insulation without losing the classic brick look of their property, which is why brick slips are such a great solution.

Brick slips are also excellent if you are living in an area where where is a high risk of mechanical impact, for example next to a busy road; they have a greater ability with withstand damage and are generally more hard wearing. Our brick slips are highly flexible (you can bend them around corners!) and come in a wide range of attractive, natural colours.

So without further ado, here is how to use brick slips on external insulation board!

Applying Brick Slips to EPS Insulation Board

EPS insulation board is a classic when it comes to external wall insulation. It’s cost effective and has excellent thermal capabilities, while also being incredibly easy to work with. EPS comes in a huge range of thicknesses, depending on how much you want to improve the thermal performance of your property (the thicker the insulation the better the insulator).

Applying brick slips to EPS is incredibly easy. The EPS boards are secured to the substrate using our EWI-220 EPS Basecoat Adhesive with plastic fixings. Once dry, the EWI-220 is used again to form the basecoat layer on top of the insulation boards. Fibreglass Mesh is sunk within the basecoat to enhance the tensile strength of the whole system, and then once a smooth surface has been achieve the basecoat is left to dry before the brick slips can be applied!

To apply the brick slips, you would use our special ready-to-use brick slip adhesive which comes in a wide range of colours for a customisable finish. The adhesive dries quickly so we recommend applying it with a notched trowel 1m2 at a time to give plenty of time to stick the brick slips on neatly.

Applying Brick Slips to Mineral Wool Insulation Board

Mineral Wool insulation is a premium insulating material. It’s class A1 non-combustible, which means it actually works to prevent the spread of flames. It’s also a vapour permeable material so will actively allow moisture to escape from the building fabric.

Mineral Wool is heavier than EPS and therefore requires a stronger adhesive and metal mechanical fixings. We recommend using our EWI-225 Premium Basecoat which is a dual purpose product, suitable as both an adhesive and a basecoat.

After the Fibreglass Mesh has been embedded within the basecoat, the brick slips can be applied in the same way you would with EPS. Simply apply the brick slip adhesive using a notched trowel to an area of 1m2, applying the brick slips as you go.

And there you have it! Applying brick slips may be slightly more time consuming to apply than a coloured render, but they do achieve a really realistic finish.

Stay tuned for more content! We upload a new blog post every Tuesday and Thursday, so keep up to date. We also release a weekly newsletter which hands out exclusive special offers and discount codes so sign up to that as well.

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applying render to SIPS

Applying Render to SIPS Panels

Structural Insulated Panels (SIPs) are a high performance building material consisting of an insulating foam core, sandwiched between two panels of OSB board. There are many benefits to building with SIPs panels, including insulation and airtightness. With SIPs panels, the insulation is highly effective due to the fact that the panels fit together tightly enough that air leakages are minimised. They’re a popular building material because the required U-values to meet building regulations can easily be achieved with a very quick speed of build.

Rendering SIPs panels can pose a bit of a challenge due to the fact that the render cannot be applied to the OSB board directly. In order to be able to render the SIPs there are various steps that need to be undertaken before the rendering can go ahead.

Installing Timber Battens onto the SIPs Panels

The very first step in applying render to SIPs panels a breather membrane needs to be secured to the external OSB panels with galvanised staples at 600mm centres horizontally and 300mm centres vertically. We recommend using the Dupont Tyvek Housewrap, as this membrane is totally vapour permeable and can be left exposed for up to four months.

Once the breather membrane has been applied, vertical timber battens need to be installed onto the SIPs panels. These are installed as a means of supporting the render carrier board which is secured to the battens, and so the size of your render carrier board will dictate where you position the battens. Once the battens are in place, you can secure the render carrier board to them using the appropriate wood screws.

The render carrier boards should have a slight gap of 3-5mm between each board. This needs to be covered over using Pavatex Render Carrier Board Joint Tape, which is another breathable membrane except this one is a self-adhesive tape and is designed for the purpose of jointing render carrier boards before render is applied directly on top. The joint tape will further secure the boards and prevent the wet materials seeping through the gaps.

Thin Coat Render Systems on SIPs

We recommend using the Premium Basecoat for rendering SIPs as this is our strongest basecoat and will therefore ensure the system is highly secure and crack-resistant (read about how to fix cracked render here). We always recommend that Fibreglass Mesh is embedded within the basecoat as a means of increasing the tensile strength of the system; each strip of mesh is overlapped by 10-15cm all the way around, and therefore once the basecoat is set the mesh should absorb any movements within the render carrier boards without cracking.

After the basecoat has set for 24-48 hours, a render primer needs to be applied. The primer used will depend upon which kind of render you are using, so if you’re going for an Acrylic Render you will use our Mineral and Acrylic Primer, but the silicone-based renders require the SiSi Render Primer. This can be painted onto the basecoat and left to dry for 12 hours, and then finally you are ready to render!

Achieving a nice render finish on SIPs depends upon thorough preparation, so by now you should have a perfectly stable and flat basecoat that will provide the perfect surface for the thin coat render. The render is applied in such a thin layer (the thickness that you apply the render matches the grain size) that any large imperfections can be quite apparent, particularly if you’ve gone for a smaller grain size i.e. 1mm. Our most popular choice for installers is our Silicone Silicate Render in a 1.5mm grain size because it is breathable and offers good coverage at a price that is great value.

The render should be applied using a notched trowel, and then it should be rubbed up using a plastic render float to bring out the texture. Once applied, leave it to set for 24-48 hours.

Wood Fibre Insulation onto SIPS Panels

If render carrier board onto battens seems like too much hassle for you, then why not use Wood Fibre insulation? The Wood Fibre can be attached directly to the SIPS panels using stainless steel wood screws and universal fixing discs. After this, you simply apply the thin coat render system on top as explained above. Not only is this a simple and easy way of doing it, it reduces the risk of condensation and also improves the thermal efficiency of the structure.

And there you have it; how to apply render to SIPs panels. We have also covered how you might go about applying render to other types of substrates, including ICF and high performance blockwork. So check out those blog posts and stay tuned for future content!

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render coverage

Render Coverage: The Ultimate Guide

When ordering materials online, customers are often unsure as to the quantities that they will require for the approximate square meterage they are working on. So, we’ve put together a guide to EWI Pro render coverage to make things more clear!

Coloured Render Coverage

Our coloured renders all come in a variety of grain sizes. This means that the grain size will determine how much coverage you’ll get out of a 25kg bucket. Bear in mind that these numbers may vary slightly depending on application; for example if you drop/lose relatively little product then you will get more out of the bucket. Coverage for our Premium Bio SiliconeSilicone, Silicone Silicate and Acrylic renders are as follows…

1mm Grain Size – 10m2

1.5mm Grain Size – 7-10m2

2mm Grain Size – 6-7m2

3mm Grain Size – 5-6m2

Monocouche Render Coverage

Monocouche render is a dry-mix render, so the coverage can vary depending upon how thick you apply it and how much water you mix in. The following coverage is therefore based upon applying the Monocouche render at a total thickness of 18mm before scratching back (two passes):

1 x 25kg bag – 1m2

Mineral Render Coverage

Mineral render is also a dry-mix render, however this is thin coat. One bag will therefore stretch between 8-10m2 depending upon application and the thickness that it is applied at. Mineral render does however need painting over with Silicone paint; one bucket of Silicone paint (15L) will cover 60-70m2.

Basecoats Coverage

Basecoats especially can be a tricky thing to calculate. Because the majority of our basecoats are multi-purpose and are used as both an adhesive and a basecoat, the coverage can vary:

Adhesion and basecoat – 2.8m2

Basecoat for rendering only – 4.5m2                                                                                                                                  

Primers

Substrate Primers

Substrate primers are applied directly to the substrate (be it brick, block or other) before any other materials are applied. Coverage of the primers is hard to estimate as certain substrates are more absorptive than others; for example if you are rendering a particularly dry substrate. Coverage for substrate primers are as follows:

Water Based Primer (5L) – 15-30m2 depending upon the absorptive capacity of the substrate

Universal Primer (20kg) – 50-70m2 depending upon the absorptive capacity of the substrate

Render Primers

Render primers are applied on top of the basecoat before the render itself is applied. These help to create a vibrancy of colour and strong adhesion to the basecoat. We have three main types of render primer, the Acrylic & Mineral Primer and Silicone Silicate Render Primer. Coverage for these is as follows:

7L bucket – 20m2

21L bucket – 60-70m2

And there you have it! Our ultimate guide to materials coverage. We hope this was useful! Keep a lookout for our latest blog posts – we upload every Tuesday and Thursday!

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rendering plywood

Applying Render to Plywood

We recently had an interesting enquiry from a customer about how you would go about rendering plywood. It’s a tricky question, because plywood really isn’t an ideal substrate to render onto, however sometimes it’s unavoidable. There are solutions for applying render to plywood, and we’re going to talk you through the best way you can do this!

Rendering Plywood: Render Carrier Board

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

To avoid this, render carrier board is an ideal solution, but the downside is that it can’t be applied directly on top of the plywood. This is because the fabrics need ventilation to allow moisture to escape and to avoid a situation where water builds up between the two materials; an air gap between the two is needed for the reduction of condensation. To resolve this, the best course of action is to staple a breather membrane to the substrate, before installing timber battens on top of the ply; the positioning of the battens will depend upon the size of the render carrier board you are using.

Once these are in place, you can secure the render carrier boards on top of the battens and attach them with wood screws. The spacing of the boards will depend on the type of render carrier board you are using, however generally you would leave 4-5mm between each board. After the boards are in place, the gaps between them need to be covered over by a render carrier board tape; we tend to recommend the Pavatex render carrier board joint tape because it’s basically an extremely breathable self-adhesive membrane which prevents water vapour from gathering in between these gaps.

Basecoating the Render Carrier Boards

Render carrier boards don’t require priming because they are specially designed for being rendered, so you can go straight into applying the basecoat with no problems. Although it is possible to use the 220 Basecoat Adhesive, we recommend using the 225 Premium Basecoat as a basecoat for extra strength and breathability. At this stage, the necessary beading required for the structure is sunk into the basecoat along with fibreglass mesh – remember to overlap each strip of fibreglass mesh by about 10-15cm.

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

Rendering the Basecoat Layer

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

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

We upload blog posts every Tuesday and Thursday, so stay tuned for more content.

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rendering metsec steel frame

Applying Render to Metsec Steel Frames

When it comes to rendering Metsec steel frame buildings, the external surface of the building needs to be taken into consideration. At EWI Store, we provide coloured render and external solutions for a wide range of substrates, and today we’re going to be discussing in detail the exact process of how to go about rendering a Metsec frame. Metsec is a company that sells cold-rolled steel for structural frames; essentially the building is constructed of a lightweight steel frame (produced by Metsec) and a variety of materials are anchored to the frame to create the buildings’ exterior skin.

There are many materials that can be used for the outside of the Metsec frame, but typically a sheathing board is secured to the steel frame. For non-residential buildings, Mineral Wool insulation is fixed to the sheathing board and the thin coat render system is applied on top. For residential projects, Mineral Wool insulation is installed within a cavity, before a render carrier board is secured to the steel frame on the outside. Quite often you can find steel frame buildings with a brick cladding forming the exterior surface as well.

We’re going to be taking a look into how you can render different substrates on a steel frame building!

Render Carrier Board: Rendering Metsec 

Once the render carrier boards have been secured to the steel battens, there will be a spacer gap of a few millimetres between each edge of the board. This is to give the boards space for ventilation and to compensate for any movement. However, these gaps need to be covered over using an appropriate render tape, or Pavatex Render Carrier Board Joint Tape; both are suitable, however the Pavatex tape acts as a vapour permeable membrane so has that extra level of breathability.

After you’ve joined the render carrier boards together using either of these methods, you can apply the EWI-225 Premium Basecoat to the surface of the render carrier board – no primer needed. Premium Basecoat is our strongest basecoat-adhesive, so we really advise using this as a basecoat for a secure render installation. The Premium Adhesive needs to be mixed with 6.5L of water and applied at a thickness of 6-8mm, before Fibreglass Mesh is embedded within the basecoat using the flat edge of the notched trowel. Each strip of Fibreglass Mesh should overlap its neighbouring strip by approximately 10-15cm.

Leave the basecoat to set for 24-48 hours, then prime the basecoat using an EWI Pro render primer. If you’re using our Silicone Silicate Render then the SiSi Render Primer is the ideal primer; simply paint it onto the basecoat and leave it to dry for 12 hours. After this, you are ready to apply your Silicone Silicate Render; this is the final layer that ensures the system is entirely waterproof and resistant to weathering. You can apply the Silicone Silicate render straight out of the bucket and trowel it on at a thickness that corresponds with the grain size; after this, rub up the surface of the render using a plastic render float to get a textured effect.

External Insulation: Rendering Metsec 

When rendering Metsec, architects will often look to create an insulated render system using a Metsec steel frame building. With this kind of construction, sheathing board is applied to the lightweight steel frame leaving a ventilated cavity in front, and then a render carrier board.  Following the manufacturer’s guidelines insulation is applied to the render carrier board using the appropriate adhesive and mechanical fixings. Once the insulation is in place, the Premium Basecoat can be used once again as a basecoat, before priming and rendering using Silicone Render.

It is commonplace to install a ventilated cavity within these residential systems, as it is a requirement for several insurance companies, although they have recently come under criticism from the general public and within the industry itself since the Grenfell tragedy. We advocate the use of Econic boards and Rockwool Mineral Wool insulation in these circumstances because they are A1 fire rated and non-combustible.  Products such as the Dupont Tyvek Firecurb Housewrap can also be introduced for extra vapour permeability and fire resistance.

And there you have it, rendering Metsec steel frames! We upload a new blog post every Tuesday and Thursday, so stay tuned for more content.

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mosaic render

What is Mosaic Render?

Mosaic Render is a bit of a luxury render, offering unparalleled durability and splash resistance. Our Mosaic Render contains quartz aggregate and is therefore known for being strong, durable and waterproof. This makes it ideal for below the DPC, where impact resistance and splash proofing are essential.

Mosaic Render is available in white, black and grey and not only looks fantastic but serves an integral function within the render and EWI system, ensuring that water will not penetrate from the ground up.

Mosaic Render as a Decorative Feature

The finish that Mosaic Render achieves is especially attractive in that the effect is almost marbled due to the fact that it is highly granulated and varicoloured. Because the product offers such a uniquely appealing finish, it is popularly used as a decorative feature for various areas of the property.

The render would produce a fantastic finish around pillars, windows and doors and on garden walls. It would also look great as a feature wall next to swimming pools because of its resistance to water and its durability. The porch area is also a very common area that homeowners use Mosaic Render, as it creates a nice contrast with the main render as a backdrop. In effect, Mosaic Render is brilliant for those looking to create a unique external facade, with close attention to detailing and high quality features.

Mosaic Render for the DPC

Another very common use of Mosaic Render is for the DPC, where durability, waterproofing and impact resistance is essential. Ensuring that an external wall insulation system is watertight at DPC level is vital to continued performance and longevity, and for this purpose mosaic offers unparalleled performance. The DPC area is also prone to plant growth and splashback, which this render can withstand really well.  

For ensuring a strong DPC, we always recommend using XPS insulation boards (because they have a higher density and are less likely to absorb water). XPS should be secured to the substrate using our Premium Basecoat, which is extra strong and breathable (this is also used for the basecoat reinforcement layer), and finally finished with the Mosaic Render.

Mosaic Render vs. Acrylic Render

As discussed, Mosaic Render is known for being extremely durable, impact resistant and waterproof. However, we also often talk about how Acrylic Render is impact resistant – so what is the difference?

Acrylic Render is a thin coat coloured render, with grain sizes suspended within the solution which give it a textured effect and a seamless colour. By contrast, Mosaic Render is made up of lots of different coloured grains which give a completely different look, these grains also make it slightly more hardwearing and waterproof.

And there you have it! Everything you need to know about our Mosaic Render. We upload a new blog post every Tuesday and Thursday so stay tuned for more content.

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re-rendering with coloured render

Re-rendering with Coloured Render

We speak to hundreds of customers who are looking at re-rendering with a thin coat coloured render, and need a solution for their existing render. Often this is because the existing render is cracked and damaged with staining from plant life and general signs of weathering. Re-rendering the property with a coloured render can work wonders on giving it a facelift and improving the general aesthetics.

In a previous blog post, we discussed how to replace pebbledash with coloured render, however in this blog we’ll be taking a look at how you might want to go about replacing an existing sand and cement render with coloured render.

Re-rendering Sand and Cement Render with Coloured Render

As is often discussed here at EWI Store, sand and cement render is extremely prone to cracking and water ingress. In general, sand and cement render is just not a suitable material for the vast majority of buildings, especially older buildings and timber frame structures; and yet it is still so commonly used. With coloured render, you are guaranteed a flexible and strong render finish because unlike sand and cement render, coloured render is applied in an extremely thin layer which means it’s much less unforgiving.

Coloured render also gives you the option of choosing a breathable render, such as Silicone or Silicone Silicate, which prevents water ingress and water vapour build-up by allowing it to escape from the building through the external walls, where it can then evaporate off the surface of the render.   

When considering re-rendering with coloured render, the most ideal place to start is by removing your cement render. This can be a pretty difficult process, as cement render is such a tough material and removing it poses a risk to the underlying substrate. Nevertheless, this is most likely the best course of action to protect your property against structural damage because Cement Render is incredibly liable to water ingress.

Re-rendering: Do I Remove or Repair my Sand and Cement Render?

If you’re considering re-rendering with coloured render, then most likely this is because your existing render has cracks within the surface. Unfortunately, as soon as the cracks start to appear then water ingress will undoubtedly follow. If this is clearly the case and your render is beyond repair then it will need removing. Once you’ve removed the render, you may need to repair the underlying substrate before you can go ahead with the re-rendering job.

On the other hand, if the render is in good condition it may be best to simply go over the top of the existing render with a coloured render system. Your installer will need to assess for any hollow patches and areas where the damage is too excessive to safely re-render. If the existing render is damaged or cracked in any way, then sometime down the line your new render may start showing cracks or it may even start falling off the wall, so ensuring the substrate is stable is essential.

How to Repair Sand and Cement Render

Often, sand and cement render was applied to buildings as a means of covering up cheap brickwork and to give an expensive-looking finish. When cracks start to appear in your render, it’s important to repair them as soon as possible in order to prevent water ingress. As soon as water gets behind the render, the process of freezing and thawing will eventually escalate the problem – leading to timber decay, internal damp and render falling off the walls.

If removing your existing render just isn’t possible without causing excessive damage to the underlying substrate, you may be able to patch repair it before applying a coloured render on top. You can use the Levelling Mortar to patch repair your existing render, as this can be applied at a thickness of up to 50mm, creating a smooth and stable surface for your new coloured render.

If your render has come away from the wall in some places completely, you can fill this using the Levelling Mortar, but we do recommend that you are careful to ensure that the rest of the render is stable enough to support a new coloured render.

Applying coloured render on top of existing render

Once you’ve established that your existing render is safe enough to re-render with coloured render, you first need to prime the substrate with the Water Based Primer. This will limit the absorptive capacity of the underlying sand and cement render and prevent it from drawing water out of the basecoat and creating a waterlogged mess underneath.

After this, you can use the Premium Adhesive as a basecoat, with Fibreglass Mesh embedded within it; each strip of mesh should overlap by 10-15cm. The reason we recommend using the Premium Adhesive is because it is much stronger than any of our other basecoat adhesives and will ensure a stable adhesion to the underlying render. Leave the basecoat to set for 24-48 hours, then you are ready to apply your coloured render.

We recommend using a Silicone Render because it’s extremely hydrophobic and vapour permeable. This means that it will prevent water ingress while at the same time allowing trapped water vapour to escape from its surface. It’s an ideal choice for old and new buildings as it’s extremely flexible so will not crack due to structural fluctuations.

And there you have it! How to re-render with coloured render. If you have any further questions or need advice about whether your property is suitable for re-rendering with coloured render, you can call our technical team who have all the technical know-how.

We upload a new blog post every Tuesday and Thursday, so stay tuned for more content!

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winter insulation materials

Winter Insulation Materials with EWI Store

Winter insulation materials… is your home prepared for winter?

Winter insulation materials are on everyone’s mind; these crisp and chilly mornings are a sure sign that the blazing heatwave of summer is over, and the dreaded task of defrosting the car every morning is drawing near. This time of year generally triggers a mass panic about where to buy winter insulation materials in order to prepare for winter, and we’re here to alleviate these stresses.

What is the solution to preparing homes for winter?

The answer to the above question is simply another question: is your home adequately insulated? If not, we’ve got everything you need. Below is an infographic all about heat loss in the home, and how external wall insulation can help.

Why choose EWI for your home?

  • Warmer in the winter
  • Cooler in the summer
  • Reduced damp
  • Reduced noise
  • Minimise energy bills
  • Extends the life of the property
  • Saves internal space

Install external wall insulation before Winter really sets in…

The best time to install external wall insulation is at this time of year, where the air temperatures are dropping but not yet freezing. EWI materials need to be used at the correct temperatures; this varies between manufacturers, but EWI Pro specify that most of their materials should be used between 5°C and 25°C. Autumn is therefore ideal for those last-minute preparations, and the good thing is that external wall insulation should only take a couple of weeks to install.

Insulating your home in the Winter? Use the right materials…

If you do happen to get to winter and discover that your insulation just isn’t enough, then it’s not too late! We have a range of winter insulation materials for installers to use during the winter months.

Winter Adhesive

Time to crack out the old Winter Adhesive. If you’re installing EPS insulation during the winter months then the Winter Adhesive is the perfect solution. It’s essentially the same as the EWI-220 EPS adhesive but it dries far quicker and is designed to be used even down to zero degrees. The Winter Adhesive is actually a bit of a lifesaver during colder climates, because it alleviates any worries about adhesive failure and resulting insulation falling off the wall.

Mineral Render

Mineral Render is a dry-mix render, so it’s in its nature to be more fast-drying. Mineral Render is intended for use in harsher climates, so it’s ideal for winter installations. It’s a thin coat render and is highly breathable, so you still get the same benefits of our other thin coat renders, the only downside is that because it’s a dry-mix it does require painting afterwards with a Silicone Paint.

Render Accelerator

If the idea of the Mineral Render really doesn’t appeal and a through-coloured render is what you want, then the Render Accelerator is the perfect solution. All you have to do is mix 200ml of the render accelerator into a 25kg tub of one of our thin coat renders, and it will speed up the drying times of the render.

The reason for render failure during colder temperatures is that it takes longer to dry and therefore water ingress becomes a problem. The accelerator completely reduces all of these worries, allowing you to install any EWI Pro thin coat render during the winter months.

Why is a fresh coat of render the best thing to have for winter?

Winter in the UK generally means miserable rain, wind and frost. Cycles of freezing and thawing can be seriously detrimental to building structures, especially if your home has an old, cracking sand and cement render. All it takes for a sand and cement render to fail is this process of freezing and thawing.

Water is easily drawn into cracks within the render before repeatedly freezing and thawing. This weakens the render and eventually, the sand and cement will fail and crumble away, leaving your wall exposed and unprotected against the elements. Worse yet is when water becomes trapped behind the non-breathable sand and cement render, moving through the walls to create damp patches internally.

A fresh coat of render installed before the temperatures really start to drop can save so much hassle. We recommend choosing a Silicone-based render, because they are extremely hydrophobic but also incredibly breathable; this means that water will not be absorbed into the render but any water vapour from inside the house can easily pass through. Silicone renders are also highly flexible, so cracking is very unlikely.

Looking for a trusted installer?

We know how hard it can be to find a responsible and reliable installer to carry out your renovation project, that’s why we have installers up and down the country who have been ‘EWI Pro approved.’ Fill out the contact form below and we will be in touch!

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