Cost of Cavity Wall Insulation

A guide of the process of hiring a tradesman to install cavity wall insulation, including the costs of labour and materials.

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Prior to insulation work taking place, a full home inspection is typically required in such projects. This is done to ensure the building is suitable for the new insulation being fitted. Contractors will drill 20 mm holes, at every 1-metre point outside the property, and fit the insulation into the walls.

Pressure gauges are used to ensure insulation is properly fitted. Of course, depending on the size of the property will play a major role in the duration of the project. Larger properties require more holes to be drilled and will take longer to complete.

Why Install Insulation

A number of reasons exist why installing insulation in the cavity wall, is a task owners would choose to undertake. For starters, new insulation means lower energy consumption. This, in turn, brings down electric, heating, and cooling bills.

Thicker insulation also helps with noise balancing. If you have loud neighbours, you won’t hear them as much as you did prior to installing the insulation. Insulation will also help improve balancing. You won’t feel vibrations when stepping or thumping occurs on the property.

In some instances, it is a requirement. If there are new codes, legislation in place, certain properties will have to be fitted with cavity wall insulation.

Additional Jobs

If you’ve decided to install the insulation, once the work is complete and cement is used to cover the holes, it might be time to consider painting your property. You don’t want unsightly holes all over the property, so painting the exterior will help with the aesthetic appeal once insulation has been installed.

If re-pointing work is desired or required, this might also be the time to consider undertaking such projects. Not only will the contractors who install the insulation likely offer these services, it will also take less time, and will be a cheaper alternative, to choosing to do this work at a later time.

If concrete gutters are present, it might also be a good idea to change them when installing a cavity wall insulation. The reason being is that with concrete gutters, leaking might ensue after the insulation is installed. If you replace the gutters, with a different material finish, you can avoid such issues, and potential water damage to your home, at a later date.

Potential Problems

When drilling holes outside the cavity walls, this can lead to structural issues down the road. If the holes aren’t properly spaced or aren’t drilled deep enough, the insulation might be improperly installed.

In addition to this, cement must be installed after the insulation is installed in the walls. This is to cover up the holes which were drilled during the installation process. If the highest quality cement/filler isn’t used, this can lead to issues with seeping. This will, in turn, cause the installed insulation to be virtually non-existent if the work is not performed by the right contractors.

Costs and Durations

For a traditional home (2-3 bedroom), you can expect to pay about £500 to have new cavity wall insulation installed. Today, many electric companies are requiring this insulation to be installed and will offer incentives for homeowners to do so. This can reduce the overall cost of the insulation installation.

In most instances, the job should be completed in a matter of hours if you hire the right professional. Of course, if you choose to paint the exterior, and do additional gutter/exterior work on the home, this is going to add to the duration of the project, and to the overall cost of the services as well. Many companies will offer discounted rates if you hire them to perform all services, rather than hire different contractors for every job/task.

It is also a good idea to check with your local electric/gas supplier if the property already has insulation installed. In homes which are 10 years or younger, the insulation is typically already installed in the home, so this is not a project you will have to undertake with newer homes.