External Wall Insulation - Getting Started - Solid Walls – How do I insulate solid walls?

Here, we present our options to insulate solid wall buildings whilst allowing them to maintain vapour permeability, as requested by Building Regulations (English Part L1B 3.8 & 3.12, Welsh Part L1B Section 12). There are two methods of insulating solid walls: externally and internally. But before you start, make sure your walls are dry - a dry wall will be 30% more insulating than a wet wall!

External Wall Insulation is installed from the outside effectively wrapping the building. This type of installation method can change the physical appearance of the building (which will usually require planning permission) and may necessitate the removal of rainwater goods and may require adaptation of the roof and wall junctions as well as window and door openings as the wall is effectively being made thicker.

It is possible to use the ecoCork plaster externally with the correct detailing, protection and environment to carbonate. The cork provides some insulation and is less disruptive than the board system. It will also help to improve weatherproofing and air tightness.

The U-value of a wall is a measure of the rate at which heat passes through the wall and so is a measure of how well insulated the wall is and is expressed in terms of “Watts per meter squared-Kelvin” (W/m2K). The lower the U-value, the better the performance of the insulation and the less it will cost to heat your home. For building regulations in an existing building, a U-value of around 0.30W/m2K or lower is recommended (but please refer to current building regulations). Carrying out a whole house energy survey is useful. Building control often allow less insulation & should follow part L1B & the British Standard 7913 reference solid wall buildings. The reduction in space, aesthetic, environmental impact of the material used and whether or not the building is listed will all have some bearing on what you ultimately choose or can practically achieve, please call our Product Advisers to discuss your requirements.