If your house was built after 1920, it almost certainly has cavity walls, and unless it was built within the last 20 years, those cavities are almost certainly empty. Adding cavity wall insulation to your home can help you retain heat and save money on your energy bills.

Cavity wall insulation can reduce the risk of moisture, condensation build up and penetrative damp problems. Cavity wall insulation also offers good sound insulation compared to a property with a solid brick wall, reducing the effect of external sound.

A cavity wall is made up of two separate walls that are joined together by a space or cavity. These two separate walls are referred to as cavity wall leaves. The inner wall is known as the internal leaf, and the outer wall is known as the external leaf. A cavity wall is also known as a hollow wall.