Monthly Archives: June 2018

Why Use Lime-Based Renders?

An Introduction to Lime

The use of Lime in building materials has a long history, dating back to the times of the Roman Empire, when lime was used for construction purposes such as mortars and render finishes. It continued to be used until the nineteenth century until Portland Cement and other cements came onto the scene, when the use of lime-based materials began to decline.

Lime is still frequently associated with vernacular buildings within areas in the south of England along The Jurassic Coast, and in places such as Bath and the Cotswolds. Lime has also recently experienced a bit of a revival in modern building and construction for use in modern renders.

So why would you want to use lime as a component in your render finish for your EWI system?

The Use of Lime in Building Materials

Lime is considered to be a ‘healthier’ building material in comparison to Gypsum and cement-based products. This is because quicklime absorbs carbon dioxide during the setting process of carbonation – otherwise known as the lime cycle. Essentially, the lime cycle is the hardening process of lime mortar and lime wash when water evaporates from lime putty and the lime reacts with the carbon dioxide present within rain water.

During this repeated cycle, the lime experiences a repeated chemical change until finally it is converted back to calcium carbonate (which is basically the original limestone). This is a slow process, but essentially what this means is that your lime mortar will eventually get stronger as time goes by. This process creates the oldest and most flexible and breathable form of lime.  

Another reason that lime is frequently used in mortars and building materials (e.g. our Lightweight Basecoat) is due to the fact that lime is a caustic. This primarily means that it has disinfectant qualities – lime mortars, renders and washes have been used to create hygienic and comfortable surfaces for buildings for thousands of years.

Lime can also be produced on a small scale; it can be produced in small quantities to meet primary demands, therefore saving energy and resources. With reference to the use of lime in the Roman era, and the gradual hardening of lime during the lime cycle – lime-based renders are also durable and have historically stood the test of time, which means that reproduction of materials for repairs is less necessary. It’s therefore a favourable option for those who are environmentally conscious but also want a durable render facade.

Lime-Based Renders and EWI systems

Lime as a component in building materials adds the benefit of breathability and vapour permeability; the greater the amount of pure lime in the building materials, the better the breathability. Because lime is porous, it absorbs and releases humidity (it breathes), therefore helping to maintain the thermal comfort of a building. This makes it fantastic for older buildings by allowing the building to breathe, and also in external wall insulation systems.

Lime-based render is an excellent addition when used in external solid wall insulation systems. This is because the breathability of lime means that it can prevent ingress of moisture, which as we know would disrupt the effectiveness of the system. This is because any kind of moisture content prevents the insulation material from retaining heat properly.  

Due to its small particle size, lime can fill minute voids within a surface, which makes it a great adhesive in comparison to cement which has large particles. Due to this, lime also binds gently to background materials, allowing for flexibility and crack resistance – although lime-based renders are more likely to develop fine, hairline cracks in comparison to larger cracks within cement-based renders.

When installing lime-based render, it cannot be applied during freezing temperatures, as this will delay the carbonation process and the render can take up to a month to properly set which may cause the render to fail. Lime-based render must also be treated with a breathable finish such as lime wash or silicone paint to protect the underlying render.

Looking for more information? Here are a couple of blogs all about when a basecoat that contains lime would be ideal…

‘Applying Coloured Render to Thermalite Blocks’

‘Sand and Cement Render on High Performance Blocks’

Stay tuned for more blog content! We upload every Tuesday and Thursday all about our EWI and render systems, answering FAQ’s and giving full and detailed product guides.

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Coming soon!


Using Housewrap as part of an EWI system

Having recently added the DuPont™ Tyvek® Housewrap to our products line up, and after mentioning it in our blog about Applying Render to a Timber Framed Property, we have received quite a bit of interest about how the Housewrap works and how you would install it as part of an EWI system. So, we thought we would go into a little bit more detail about it for your benefit!

What is Housewrap?

At EWI store, we offer two different types of housewrap: the DuPont™ Tyvek® Housewrap and the DuPont™ Tyvek® FireCurb® Housewrap. So what are they?

Both membranes offer the same levels of breathability and vapour permeability, however with the exception of the fact that the FireCurb® Housewrap offers users an added layer of fire resistance. This is a fantastic benefit, especially when installing on timber frame properties or alongside our Mineral Wool insulation system which is also highly fire resistant.

In terms of general performance characteristics, the Housewrap and FireCurb Housewrap are breather membranes that offer unsurpassed performance for improving the breathability of a building. These membranes are designed to be compatible for use with properties built with timber frame, metal frame, stone, masonry and more. Both housewraps are extremely lightweight and can essentially be stapled onto a substrate – such as OSB board.

We talk a lot about breathability here at EWI store, which is why we are so keen on the DuPont™ Tyvek® Housewrap. The membrane basically works by allowing water vapour and moisture from the interior of the property to escape, while at the same time providing a barrier against the elements. It therefore allows the building to breathe, reducing the risk of damp and condensation and improving thermal performance.

Because breathability is such a key component to the thermal performance of a building (moisture and water vapour decreases the thermal efficiency dramatically), the housewrap membrane is a fantastic one to use in conjunction with an EWI system. This is because it adds that extra amount of support to the system. And even better, it can be fixed directly to the insulation boards!

Using Breather Membranes with EWI

As previously mentioned, breather membranes work wonderfully in conjunction with EWI. This is because they are so lightweight, they will not be detrimental to the structural integrity of the system and they can be attached directly to the insulation boards.

For example, if you were to install Housewrap onto a timber frame property, then you would apply the housewrap to the OSB boards by either stapling them or using fixings. After this, you would carry out your EWI installation as normal – laying the insulation over the breather membrane and then installing the basecoat and render finish.

Recap: Advantages of using Breather Membranes

  • Added vapour permeability and breathability
  • Improves the thermal efficiency of your property
  • Easy to install
  • DuPont™ Tyvek® FireCurb® Housewrap offers extra benefit of fire resistance
  • Lightweight and Flexible
  • Offers support to an EWI system
  • Can be installed directly on top of insulation boards
  • Can be used for a wide variety of building structures

We upload new blog posts every Tuesday and Thursday, all about our product range, along with technical questions and customer FAQ’s. Stay tuned to keep up to date!

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Dryzone Damp-Proofing Cream for the DPC

We’ve recently added Dryzone Damp-Proofing Cream to our product range, and we have to say that we think it’s a fantastic product. Dryzone is designed to create an artificial DPC, which prevents rising damp from permeating the building structure. Rising damp can be seriously detrimental to structural integrity, especially if you intend to install external wall insulation on your property, so Dryzone Damp-Proofing cream can come in really useful as a safeguard against this.

What is a DPC?

A DPC is an in-built barrier within your walls which is designed to prevent moisture rising through the walls at ground level. Typically, a DPC is created using a moisture resistant material; slate is a traditional material commonly found in older properties with existing DPC’s, however these days you can also find DPC’s made of other durable and water resistant materials such as plastic and rubber.    

In the case of really old properties, the DPC can fall to disrepair and as a result damp can permeate through the material. This is where a chemical DPC such as Dryzone Damp-Proofing Cream comes in really handy.

What is Rising Damp?

When a property has no DPC, or even a DPC that is in disrepair, it is vulnerable to rising damp. Rising damp occurs when water travels upwards from the ground through capillary action. This can eventually cause damp patches on the internal walls and floors, damaging plaster and warping floorboards. It’s a pretty common and worrying issue for properties, and the only way to stop rising damp in its tracks is with a DPC.

What is Dryzone Damp-Proofing Cream?

Dryzone Damp-Proofing Cream has revolutionised the treatment of rising damp, allowing users to create an artificial DPC by drilling holes at DPC level, and then injecting the cream into these holes using an applicator gun. The Damp-Proofing Cream then absorbs into the wall, creating a chemical barrier that prevents damp from rising up the wall.

Dryzone Damp-Proofing Cream: An Overview

  • Quick to install
  • Easy to install
  • High strength formula
  • Low hazard and non-flammable
  • No spillage and mess during installation
  • Can be used on a range of substrates: brick, stone and rubble construction

Dryzone Damp-Proofing Cream and EWI

As we know, in order for an insulation system to work effectively and maintain a high thermal performance, it needs to be free of moisture. This is why eliminating problems with damp before installation is vital, not only in terms of performance but also for structural integrity.

Stay tuned for more blog content! We upload every Tuesday and Thursday all about our EWI and render systems, answering FAQ’s and giving full and detailed product guides.

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Why is EWI the Future?

The market for external wall insulation in the UK has rapidly expanded over the last few years, with more and more homeowners becoming aware of the process as a solution to energy efficiency. There are some out there who are skeptical about the future for external wall insulation, with negative doubts towards the technology and the reliability of retrofitting.

In this blog post we thought we would talk a little bit about why we think that external wall insulation has a long future ahead!

New Build Properties

These days, more and more people are worrying about the pros and cons of investing in new builds. The UK housing stock is rapidly growing, and the quality of newly built houses are under scrutiny from potential buyers and the media. While today’s new builds must achieve the regulatory U-values for a property, some homeowners are reluctant to invest in newly built homes due to concerns surrounding the quality of build, static resale values for at least five years and premium prices.

The appeal of investing in a quality older property, and instead spending the money on doing it up and improving its energy efficiency in other ways (and consequently improving its value) is an appealing choice for many homeowners. Among one of these methods of improvement is external wall insulation.

Growing Interest in Passivhaus Standards

EWI can contribute to passivhaus standards which is becoming a new trend for building design. Awareness of the passivhaus building style is gradually growing within the UK, with environmentally aware homeowners becoming more and more intrigued about how this level of insulation might be mimicked.

Enter external wall insulation – a way of improving the energy efficiency standards of a property by simply retrofitting it to the existing building. EWI may not make your home a Passivhaus, but it can certainly work wonders on dramatically improving your U-values and energy output.  

Large Quantities of Solid Wall Properties

To this day there are approximately 9 million solid wall properties in the UK. This means that 9 million homes do not have adequate insulation and are therefore functioning inefficiently.  External wall insulation is the best solution in these circumstances, since internal wall insulation simply doesn’t have the same high performance results.

Rising Energy Prices

Energy prices go up by around 5% each year. As household bills become more expensive, heating the home with traditional heating methods will become more and more costly. People are therefore better off focussing on effective insulation to combat the need to excessively heat the home and rack up the pricey energy bills.

Growing Technology

Because external wall insulation is a growing construction process, the current technology is extremely up to date and is only getting more advanced. The effectiveness of the system will only keep improving and here at EWI store we hope to keep growing with it. Take for example the groundbreaking thin coat render systems, including silicone render technologies that provide unbeatable hydrophobic properties.   

EWI is also growing in a appeal to those who may not have ever considered anything of the sort – at the beginning, there were worries that the EWI would ruin the external walls of the property, when in actual fact it protects them against weathering. There has also been advances in research about different substrates and the best materials for them. For example timber frame properties need to breathe, therefore breathable materials (e.g. wood fibre insulation) are really on the rise.

The continued visual and aesthetic appeal of EWI is also of interest to homeowners. There are now many cases where EWI has vastly improved the look of the property and the technology behind this is continuously developing. Take for example our Acrylic brick slips and our wood effect render. The wood effect render is actually a really clever way of mimicking timber beams without the hazard of the wood rotting or posing a fire risk.

UK Housing Situation

As the UK housing crisis continues, people are more concerned about investing in the longevity of their homes – ensuring that they last and that they are saleable. Investing in EWI is a great way to extend the life of a property because, as previously mentioned, it protects the external walls of the property. It can also improve the value of the property due to higher EPC ratings, lower U-values, lower energy bills and increased visual appeal.

Increased Awareness of Climate Change

The media and the government are currently paying a lot of attention to climate change and how we can combat this. As a result, there has been a huge surge in people who are keen on making a difference in combating climate change and saving energy. This is encouraging growth in interest in energy saving from an environmental perspective as well as money-saving. Homeowners are keen on external wall insulation because with EWI the need to heat their homes is decreased dramatically, thereby reducing their carbon footprints.

Changing Energy Efficiency Standards

Required energy efficiency standards are going to get a lot tighter as climate change continues. 2018 has brought the landlords minimum energy efficiency standards (MEES) regulations. The main aim of the MEES is to prevent fuel poverty by ensuring that rental properties have an EPC rating at a minimum of E.

This is the first in energy efficiency regulations and we hope that more regulations such as these will be brought forward to help cut down on inefficient energy usage.

Growing Awareness

Excitingly, general awareness of external wall insulation is growing, and as a result more and more installers are offering external wall insulation install jobs. Installing EWI is a complicated procedure and needs to be done properly. We recommend that you always choose trustworthy installers to carry it out, and we have a database of trusted installers all over the country who we can point you in the direction of. So get in touch and we can pass you on!

Stay tuned for more blog content! We upload every Tuesday and Thursday all about our EWI and render systems, answering FAQ’s and giving full and detailed product guides.

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We’re Exhibiting at the Homebuilding and Renovating Show!

We are thrilled to say that we will be exhibiting at the Surrey Homebuilding and Renovating Show on the 30th of June and 1st of July! We’re excited to get talking to lots of homeowners out there who are interested in upgrading both the look and the thermal performance of their properties.

Come and see us at the Homebuilding and Renovating Show, Sandown Park, Surrey. Our stand number is E326, so come and have a chat about all things Render and EWI. You can grab your two free tickets by clicking the following link:

We look forward to seeing you there!


monocouche scratch render cost

Monocouche Scratch Render Cost Per Square Metre

Customers who are interested in using our renders always ask exactly how much per square metre e.g. Monocouche Scratch Render cost per square metre. The answer varies from render to render and is not limited to how much the render itself costs per square metre.

To get a full picture of how much the materials will cost per square metre, it’s necessary to take into account how much for mesh, beading, basecoat, primer and more. This week we are going to look at how much the materials for a monocouche scratch render installation will cost per square metre.

What is Monocouche Scratch Render?

Monocouche scratch render is a polymer modified, decorative, through-coloured render. As opposed to our thin coat renders which have different grain sizes and come ready to apply, the monocouche render is a thick coat render and comes as a dry mix – so it requires mixing with water before application. It’s much more traditional because it is applied at a similar thickness to a sand and cement render, however, our monocouche render is breathable – therefore allowing water vapour to escape through the render.

Because it provides more of a traditional finish on a property (it gives a chalky, sandstone effect) monocouche is a popular render choice. The finish that monocouche offers is different to our coloured renders. The thin coat renders have different grain sizes within the render which offer a textured finish, while the monocouche is smooth until you scratch it back to achieve a dappled effect.

How much is Monocouche Scratch Render Per Square Metre?

So, to work out exactly how much the monocouche scratch render will cost per square metre, you first need to measure up the property to work out the approximate square meterage. So to work out the square meterage of your external walls, you simply need to go outside and measure the length and height of the wall then multiply those two numbers together. This needs to be repeated for each wall you intend to render and then totalled together. This will give you the external wall area.

Once you have the external wall area, we need to work out how much each of the materials will cost per square metre, then add this all together for a total materials cost per m2.

Best practice is to prime the substrate before applying any kind of product. Assuming the substrate is a standard masonry, we recommend using our water-based primer. This primer essentially prevents the substrate from absorbing too much water out of the render which can lead to cracking and damage. The water-based primer costs approximately 30 pence per square metre. (view our full primer guide here for a comprehensive overview of each primer).

When it comes to the actual monocouche render itself, generally we advise that our monocouche scratch render covers approximately one metre squared per bag of render. That means that the number of bags of monocouche that you buy should more or less match the square meterage of your property. Monocouche render is £11.33 per square metre.

Our monocouche system requires that installers embed fibreglass mesh within the first layer of render to enhance tensile strength and crack resistance. Taking that into account, the fibreglass mesh costs approximately 70p per square metre.

Beading is also embedded within the first layer to reinforce weak points within the render, e.g. around corners, windows and doors. Beading generally costs £2 per square metre, although bear in mind this can vary between properties.

So, to add all of this together the total cost of monocouche render per square metre is approximately £14.63 per m2.

Buying Monocouche Scratch Render

When you order your monocouche render with EWI Store, we can offer next day delivery and our specialist technical advice service. We believe in the importance of being able to offer our customers the benefit of our knowledge and so all of our sales team are well experienced in the use of our products and will be able to give the best advice on how they are best applied and how much you will need. We’ve also written a blog post about coloured render cost per m2, so check that out for a comprehensive overview of that particular system!

Stay tuned for more content! We upload a new blog post every Tuesday and Thursday all about our renders and our External Wall Insulation Systems. Also follow us on Facebook, Instagram and Twitter for exclusive updates!

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Maintaining my EWI

Maintaining your EWI can present a bit of a challenge for many EWI-owners out there who are keen to maintain the condition of their investment. The majority of our content here at EWI store is focussed around installation of external wall insulation and use of our products. Nevertheless, the lifespan and performance of our systems is of utmost importance to us – we want our customers to be happy with their external wall insulation system for the duration of its lifespan, and therefore aftercare and maintenance is an important topic to discuss.

There are a few things that customers must be aware of after their EWI has been installed to ensure that it lasts and performs to the highest of standards, so keep reading for more info…

Guttering and pipes

Part of maintaining your EWI means that you will need to keep a close eye on your guttering and pipes. Continuous leaking from rain gutters will cause damage and staining to your render finish in that area. If you notice any damage or staining then call in a professional to get it fixed ASAP and follow our instructions (further down) on how to clean the system.

Plants and soil levels

We love a climbing Wisteria as much as the next person, but unfortunately climbing plants will eventually create staining on your render finish. The same goes for low level plants and shrubs – keep these at a distance from the render and try to keep soil levels as far below the system as possible as this can cause splashback during wet weather.

Silicone Sealant

Unfortunately, silicone sealant will not last forever and will at some point need replacing. Our approved installers will aim to use as little silicone sealant as possible due to its shorter lifespan. Despite the fact that silicone sealant is relatively easy to fix, it’s pretty important to get it right, so it’s probably best to call in your installer to replace it.

Fixings and Aesthetic additions

It is inevitable that you will want to fix something to the external walls of your property. This could be items ranging from satellite dishes to clothes lines, but the important thing to remember is to use the appropriate fixings and ensure that they pass clean through the EWI and into the original wall surface.

This is because it is not safe for the EWI to carry the weight of the fixing and it could result in damage and injury. Once installed, the fixings must be sealed using silicone sealant around the openings where they penetrate into the EWI system.

We also recommend that you choose stainless steel fixings so avoid rust transferring onto your render finish.


At some point in the future you will most likely want to clean your windows and use a ladder to access them. If you need to use a ladder at any time then if possible you should use a free-standing ladder so that it is not leaning directly against the EWI. This is because the pressure that the sharp edges of the ladder will apply to the EWI could cause damage and puncture the system.

If you do need to use a leaning ladder, then ensure that it has a spreading board at the top to minimise any risk of damage and do not drag the ladder against the system. As the homeowner, it’s essential that you communicate this with anyone who is coming to do work on your home that may require the use of a ladder.


Cleaning your EWI system is a fairly simple step in keeping the facade looking fresh. We recommend that if your EWI is looking dirty on the exterior you may need to give it a clean using mild soapy water and a cloth or sponge, or a very gentle power wash. If this is not enough and your render finish is experiencing some biological contamination then we recommend the use of our Fungicidal Wash. Simply apply the wash to the contaminated areas or the entire facade and leave for 24 hours to work its magic.


You may find that over time the render finish on your external wall insulation system will show signs of needing a refresh. We recommend that you first clean the render, and then if the render still looks like it needs a fresh coat of paint then we suggest that our silicone paint is applied over the top of the existing render finish.

So there you have, your basic EWI maintenance guide. We always recommend that if you are unsure about something to do with your EWI system, and especially if there are unusual cracks in your render then it’s best to call out a professional rather than attempting to repair it yourself. Alternatively, do call us for any further advice about your system, we are always happy to help!

Stay tuned to our blog! We upload a new blog post every Tuesday and Thursday all about EWI and render!

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Can I Install New Windows after EWI?

Installing windows before or after EWI?

We receive many questions from customers about whether it is possible to install new windows at a later date than their EWI installation.

It’s a tricky question, because in an ideal world it’s best to leave the external wall insulation undisturbed by installing new windows first. However, for some homeowners this just isn’t possible for reasons pertaining to added costs, or simply because their current windows at the time of installation were in a good condition. It is possible to install new windows after your EWI installation, but we would really advise that extra care is taken.

When installing EWI, new windows are often installed before the insulation to ensure that the EWI is fit snug against the window panes. The best kind of windows to install ahead of your EWI installation are windows with trickle vents. This is because with the added insulation, gaps in the windows can be blocked up – which can increase the chances of condensation build up, so trickle vents are fairly necessary to alleviate this.

It does make sense to install new windows before you go ahead with an EWI installation, because it saves you having to bother with carefully removing the windows at a later date – at the risk of damaging the insulation. However, we are aware that often the windows may be perfectly okay at the time of installation, but for varying reasons may not outlive the 25 year life of the external wall insulation.

How do I install windows after EWI?

Unfortunately, replacing your windows after external wall insulation is not the easiest job and you will need to make sure that you choose a highly rated professional to carry out the task in order to avoid as much damage as possible.

If you are very lucky and your windows installer does a perfect job and measures the windows exactly right, then they can be easily fitted into the wall and then sealed up against the insulation. Unfortunately, it is really common for windows to be slightly under or over sized and that means either cutting back some of the insulation or adding insulation to fill out any gaps. In these situations it’s unlikely that you will get away with it without any marking or scarring of the external wall insulation, or having to repair it which is very difficult to do.

As you can imagine, this is all going to add an extra cost to the job. So it’s definitely worth thinking about how old your windows are and whether it’s viable to get them replaced before your external wall insulation installation.

The key thing is to ensure your installer is as careful as possible to not damage the rendering when taking the old windows out. We recommend removing them from the inside of the house to avoid knocking the render on the reveals. If any damage is done to the reveals, this is usually fairly easy and cheap to repair. Unfortunately if any damage is done to the main elevation, this can prove difficult to patch without leaving a scar on the wall. And it may be necessary to re-render the whole elevation.

If you have any further questions, then please comment below or call our technical team! Stay tuned for more content, we upload a new blog post every Tuesday and Thursday all about EWI; from answering customer queries to detailed product information.

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How can I improve the EPC rating of my property?

Can External Wall Insulation Improve your EPC Rating?

A lot of people look to improve the value of their homes in terms of aesthetics – updating the kitchen, bathroom, etc. However, people often overlook how much improving the EPC rating of your property can increase its value. There are many ways you can do this, and installing EWI is one of them.

We often talk about how external wall insulation can increase the value of your home, whether it’s through the improved external appearance or the dramatically increased energy efficiency. In actual fact, by law every property that is built or sold needs to have an EPC rating. This stands for Energy Performance Certificate rating and essentially means that your home is rated on a scale from A to G for how efficiently it performs – A being amazing and G being terrible.

The EPC of your property can have a direct effect upon the value of your property. This is because if someone were to buy your property rated at a G level, then they would have to spend more money on it to improve its energy performance and increase its comfort. On the other side of things, if you were to invest in improving the EPC of your property, then subsequently you could benefit from its increased value.

Higher EPC ratings and property value

Energy prices are going up and up every year, and as a result people are a lot more willing to invest in a property which will cost them less in the long run in terms of energy bills, so improving your EPC rating is a sure-fire way to improve the saleability of your property (it’s also great for the environment by reducing your carbon footprint). The good thing about external wall insulation is that you get to increase the value of your property through improving your EPC, whilst at the same time increasing its appeal due to its improved aesthetics.

We see a lot of people installing EWI onto a whole range of properties with different aesthetics and different EPC ratings looking to get increased energy efficiency with EWI installations. The most common property that we see installing EWI are solid walled properties with really low EPC ratings. EWI can increase your EWI rating by 10-20 points or more. According to the government website, if you are a homeowner in London and you raise your EPC rating from a G to an E, you can allegedly increase your property value by around £41,808 (based upon average sale prices in the region).

Another useful thing about EWI is that you can install the insulation boards in varying thicknesses. This basically means that the thicker the insulation boards you install, the more thermally efficient your house will become. So you can choose the amount of insulation you’d like to install to the exterior of your property based on how much you want to raise your EPC rating by and how much you are willing to spend. You can also install EWI onto just one wall, so if part of your house is solid walled and the rest is cavity insulated then you can certainly externally insulate the solid wall section with EWI.

People whose properties are already fairly high up on the EPC rating scale may just want to just go for a 20mm insulation board. On the other hand, if you are on the opposite end of the scale, rated at a G, then you can install insulation boards up to a thickness of 100mm. 100mm of EPS installed to the exterior walls of your property will more than likely boost your EPC rating dramatically.

Nevertheless, we will say that if your property is really low down on the EPC scale then external wall insulation alone won’t be a one-stop solution to raising your EPC. You will need to have other energy saving methods in place, such as loft insulation, working in conjunction with the EWI. It seems very obvious, but if you install EWI but then leave your loft completely bare of insulation, then it’s essentially the same as wrapping your house up in a coat but leaving the hat off – the heat still has an enormous escape route through the roof and your EWI won’t be as effective. As a result, your home won’t be very energy efficient.

It’s all very variable from case to case, so definitely get your property assessed and see what is recommended for you!

Will EWI make my property compliant with MEES?

There’s a lot of talk about EPC ratings at the moment due the new landlord legislation (MEES) that we talked about in this post. The MEES (Minimum Energy Efficiency Standards) legislation basically dictates that from the 1st of April 2018, landlords with tenants who are renewing/beginning a contract after 1st of April will need to ensure that their properties have a minimum EPC rating of an E or above. This has caused quite a stir because a lot of landlords are confused as to how they can improve their EPC ratings to comply with the MEES. As a result, we’ve had quite a few phone calls about whether or not external wall insulation will be able to bring their properties up to an E rating.

If you need to raise your EPC rating and you’re concerned about how you can do this, then solid wall insulation is a great way to go because it acts as a thermal envelope for your entire property. We really recommend that before you go ahead with installing external wall insulation you hire a surveyor to check out your property in order to give you the green light to go ahead with EWI in time for the MEES.

Once you’ve had the property checked and approved and are looking to move forward with your installation, then give us a call! Here at EWI Store we have a large team of approved installers all over the country who we can put you in touch with and who will be able to advise you on what thickness of insulation to go for and which coloured renders to choose. Installing external wall insulation is a really great investment and is likely to draw more tenants in for the future. This is because if your property is cheap to run then it will attract more tenants.

The good thing about EWI is that it takes a really minimal amount of time to install (two weeks depending upon the weather). It also causes no disruption to the inside of the property because all of the work is done to the exterior, so if you have current tenants living in the property there shouldn’t be a massive disturbance. If your property is situated along a busy road, this may be something that is considered to be undesirable from a tenants point of view. Our Mineral Wool insulation system vastly improves the acoustics of a property and reduces the amount of sound entering your property.

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