External Wall Insulation

External wall insulation is the less known version of home insulation that is available to homeowners. This article will hopefully explain everything you need to know about external wall insulation, and aid you in deciding whether this form of insulation is appropriate to your home.

What is external wall insulation?

External wall insulation involves fixing insulation to the external walls of your property, which is then covered with a special render or cladding to reduce the heat loss through your walls (please see diagram and video clip). This insulation system can cut your heating cost quite dramatically by helping to stop heat from escaping through your external walls.

The insulation works by essentially wrapping the exterior of the house in a thermally resistant package (Seen in diagram above) These layers prevent about 30% of the energy that would normally be lost through the walls should your home not have external wall insulation.

Insulation is measured and rated by the R- Value which is the measurement of thermal resistance. The larger the R-Value the greater the thermal resistance is. Therefore, if the R- Value is higher it means that the insulation effectiveness and resistance is greater which prevents heat loss.

The Benefits of External Wall Insulation

• Installation of the external wall insulation does not affect the interior of your property because all the work is carried out on the exterior of your home. Therefore, it does not affect your everyday routine while the insulation is being installed.
• Saves you on your heating bills by reducing heat loss by up to 30%
• Improves the weather protection of your home because the exterior render finish is waterproof.
• Improves the sound resistance of your home
• There are different render finishes available to match your homes style.
• Any poor rendering or cracks in the wall will be covered up by the external wall insulation, this will help to make your home more air-tight.
• If you live on a terrace it is possible to have all the properties done at one time all-together.
• Internal and interstitial damp and condensation is prevented from within your property.

External Insulation Considerations

• Despite the ease of installing external wall insulation at your property there are considerations because external wall insulation can be a costly investment, especially if scaffolding is required. Therefore, the following points need to be taken into consideration before making the decision of installing external insulation at your home.
• There needs to be good access to all exterior walls for the work to take place.
• Your property’s walls need to be structurally sound before work can be undergone. If they cannot be repaired then external wall insulation is not for you.
• You may require planning permission to install the exterior insulation and external insulation may not be permitted for listed buildings or properties in conservation areas.
• If there isn’t sufficient roof over-hang then your exterior wall needs to be sloped, weatherproofed and new guttering fitted to accommodate the insulation. Down pipes etc. also need to be dealt with and window trickle vents and damp proof course must not be covered.