External solid wall insulation is the less known version of
home insulation that is available to home owners. This article will hopefully
explain everything you need to know about external solid wall insulation to aid
you in deciding whether this form of insulation is appropriate for your home.
What is external solid wall insulation?
The insulation works by essentially wrapping the exterior of
the house in a thermally resistant package, seen in the diagram above. These
layers prevent about 30% of the energy that would normally be lost through the
walls if your home didn't 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 insulating
effectiveness and resistance is greater which prevents heat loss via your
property’s walls.
The benefits of external solid 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 whilst the insulation is being installed.
- Saves you money on your heating bills by reducing your home’s heat loss by around 30%.
- Improves the weather protection of your home because the exterior render finish is waterproof.
- Improves the sound resistance of your home. The layers not only reduce heat loss by also provide great sound proofing.
- There are different render finishes available to match your home’s style, such as, Georgian and Victorian.
- Any poor rendering or cracks in the wall will be covered up by the external wall insulation. Therefore, having insulation installed will help to make your home more airtight.
- 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 of £9500 to £13000 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 suitable 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.
Worth considering before the work starts
Before you begin installing your external insulation it is
worth seeing if you qualify for the work to be carried out for free by getting
in touch with your local Green Deal assessor. The Green Deal is a government
initiative that provides hard-to-treat properties and the vulnerable with free
insulation. Therefore, if you live in a solid wall property (a building built
pre-1930) or have a hard-to-treat cavity (found in properties built pre-1950)
you could qualify for External solid wall insulation, internal solid wall
insulation, loft insulation and renewable heating systems 100% funded.
Therefore, it is worth asking your local Green Deal advisor if your property
qualifies for free insulation.
