Cavity wall insulation is the process of filling the cavity between brick walls in a property with insulating material. This reduces heat loss from the building and can dramatically cut energy bills. It is most commonly done in older buildings or those being altered but can also be installed in new build properties.
This type of insulation is one of the most effective ways to reduce the amount of heating that is needed, saving a significant amount on electricity bills. It is especially important during the winter months when heat escapes through the walls through convection, one of three ways that heat travels.
There are a number of different materials that can be used to insulate the walls including polystyrene beads, mineral wool and polyurethane foams. These are injected into the wall cavities using specialist equipment and can be applied to both brick and timber frame constructions.
The most popular insulation is made of expanded polystyrene beads or EPS. This is a small bead sized material that is pumped into the cavity wall and bonds with a chemical bonding agent. It is a relatively inexpensive insulation and is water resistant.
Another type of insulation is cellulose which is a more eco-friendly option that is blown into the cavity with special equipment. This is basically old newspapers and other paper-based products that have been shredded and mixed together then dried out to make it an insulation material.
When choosing an installer to carry out this work, look for one that is registered with the CIGA (Cavity Insulation Guarantee Agency) and has a CIGA 25-year guarantee. This will give you peace of mind that the installation is covered if anything goes wrong.