Modern homes built after 1924, usually have a space (called a cavity) between the internal and external walls. This was originally designed to stop rain water reaching the inside of the property, however today this gap can be filled with insulation to minimise heat loss and make your property much more energy efficient. After 1982, building regulations changed and required insulation to be fitted in the cavity at the time of build.
Homes built before 1924, were often constructed with solid walls and lose even more heat than cavity walls! This can be reduced by installing insulation on either the inside or outside surface and is one of the most impactful changes that can be made to a home. This method of insulating walls is significantly more expensive and disruptive than cavity insulation, as it can sometimes require substantial building and decorating work.
Recent research, carried out by the Department of Energy and Climate Change (DECC), has shown that only 58% of all properties with cavity walls in the UK have been insulated. People in the remaining 42% are pouring heat and money out of their homes.