What is external wall insulation?

External wall insulation systems totally encapsulate the building structure which is the most effective way of insulating a building, with least risk of cold bridging and interstitial condensation.

EWI systems require careful planning and system designs of the highest standard. Once external wall insulation has been completed this can give your house a whole new look and appearance.

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External wall insulation is a layer of insulation on the external wall to keep heat in and cold out

What is the difference between External wall insulation and Cavity wall insulation?

If your home was built before 1920, the external walls are probably solid rather than cavity walls. Cavity walls are made of two layers with a small gap or ‘cavity’ between them. Solid walls have no such gap, so they let more heat through. Solid walls can be insulated – either from the inside or the outside.

This will cost more than insulating a standard cavity wall, but the savings on your heating bills will be bigger too.

How do Eco-Green Deals install External Wall Insulation?

We can plan and install EWI with minimum disruption, as we work with leading system designers leading the industry our installation process once qualified and ready customers can expect an install to be as simple as;-

  • First our strip out team would attend to remove and prepare all building furniture such as satellite dishes and vents.

  • Secondly our installation team would install a layer of insulation material to the external wall with adhesive insulating the entire external wall area of the property.

  • astly the property would be coated in render and your building furniture reinstated giving your property the look good factor as well as being a warmer home.

External Cavity Wall Insulation Facts

Type of solid wall insulationSavings per yearTotal cost in
Carbon dioxide
saved per year
Around £460£5,500 to £8,5001.8 tonnes
ExternalAround £490£9,400 to £13,0001.9 tonnes

Estimates based on insulating a gas-heated, semi-detached home with three bedrooms
*Costs may vary significantly depending on level of work required

*SOURCE: Energy Saving Trust 2013

Frequently Asked Questions – External Cavity Wall Insulation

External wall insulation (EWI)

A layer of insulation material is fixed to the outside walls of your house. It is then covered with a special type of render and can be finished to your liking — smooth, textured, painted, tiled, panelled, pebble-dashed, or finished with brick slips.

What are the benefits of EWI?

EWI dramatically reduces the amount of heat lost through the walls of the building by trapping heat and preventing it escaping to the external atmosphere. The insulation boards that are installed have excellent resistance to heat transfer, meaning more of the heat you put into the building stays in the building, resulting in lower bills.

How much does it cost?

Each building will have specific requirements, so it is difficult to give a guide-figure. Instead, Eco-Green Deals is committed to giving you a free survey and quotation so you will have an exact figure, meaning you can budget from your own resources or explore ADDITIONAL grant routes with our help.

How long does the work take to install?

A typical installation takes 1 – 2 weeks. The installation is weather-dependent, however. The basecoats and renders cannot be applied when the outside temperature is below 5°C, nor in periods of extremely hot weather. Also, the system should be protected from the rain. We will take all steps to protect your installation, but there may be times when we have to withdraw from site due to extremes of weather. Should this happen, we will communicate fully with you so you are aware of any re-scheduling.

How long does EWI last?

EWI is expected to last 30 years + and in most cases exceeds its expectancy.

Is the work guaranteed?

You will receive a 10 year product and workmanship guarantee. For additional peace of mind, this can be extended (at cost) to 25 years.

What about fixing things to my walls after the work is finished?

You will need to use fixings that penetrate through the external wall insulation and into the substrate of the building, i.e. the original wall

Apply for Fundingarrow-big

Eco-Green Deals work on many schemes and are most likely able to access some form of funding or another to assist in the installation of your External Wall Insulation. We advise you don’t delay and call our office for further information where we would love to assist you.