Closeup of cavity insulation within a wall

Cavity Wall Insulation Problems

Cavity wall insulation is well known for providing a cost-effective method of reducing heat loss from your property. However, if the cavity insulation is not installed correctly then it can lead to damp problems further down the line.

More and more houses are being built to ensure that they are more energy-efficient and greener but unfortunately, this can also lead to damp issues such as penetrating damp.

What is Cavity Wall Insulation?

Properties are built with either cavity walls or solid walls. A cavity wall has a gap of 50 mm from the exterior wall to the inner wall of the building. Cavity walls are insulated through injecting insulation material such as mineral wool fibre, foam or bead polystyrene to the fill gap and prevent heat loss.

If the property has already been constructed, then cavity wall insulation will be installed by drilling into the outer wall of the property and inserted via the drilled holes. These holes are then filled in to match the brickwork of the building.

Cavity wall insulation usually takes around 2 hours to install but this will differ from property to property and is dependent on the size of the house and other factors as well.

Cavity Wall Insulation Causing Damp Problems

Problems related to damp from cavity wall insulation are predominantly due to the poor installation or the lack of understanding that the property should not be fitted with cavity wall insulation in the first place.

The suitability of cavity wall insulation being installed is one area that is often overlooked. External brickwork can as a bridge for moisture to penetrate its way through the outer wall to the inner walls of the property. This process then leads to penetrating damp problems. Before installing cavity wall insulation, it is advisable to check to see if it could lead to damp issues further down the line.

Condensation can also occur as a result of having cavity wall insulation. Cavity walls are used to reduce the amount of heat escaping the property, however, if there are gaps in the walls this will mean the walls remain cold.

When warm moisture-laden air starts to build in the house, from carrying out day to day activities (e.g. boiling a kettle or having a shower), the warm moisture laden air will land onto cold walls causing condensation which will start to build up leading to issues such as black mould in the property.

Is My House at Risk to Damp Issues from Having Cavity Wall Insulation in Place?

Having damp problems resulting from the installation of cavity wall insulation is not something that happens too often, but it is worth checking before having cavity wall insulation installed. It is always best to prevent the problem from occurring rather than rectifying the problem afterwards.

Most houses are suited to having cavity wall insulation installed, but it is very much dependent on how well maintained the exterior walls of the property are.

If the house is weatherproofed, then you will not be vulnerable to letting moisture in and soaking the insulation and as a result won’t have damp problems at a later date as a result of the insulation. This will mean you should gain the full benefit of having cavity walls, so the energy bills at the end of each month will be reduced.

To help you identify if you are at risk of damp issues as a result of installing cavity wall insulation we have compiled a list of questions below to see if your house is at risk for potential damp issues from having cavity wall insulation installed:

  • Is the property exposed to wind driven rain?
  • Is the house sheltered by buildings or trees?
  • Are the external walls poorly constructed or maintained?

If you are answering yes to any of these questions, then it might be worthwhile having second thoughts on whether cavity wall insulation should be installed at your property.

If the property looks to suffering from penetrating damp issues resulting from cavity wall insulation, then check out our penetrating damp treatment page for helpful tips on reducing the damp problem.

Contact A Damp Expert

If you find cavity wall insulation is causing damp problems at your property, then we are here to help. Having a damp specialist provide an inspection will ensure the damp issue is fully diagnosed so the right treatment can be used to get rid of the problem.

We have a team of professionals who are fully qualified by the Property Care Association you can be rest assured that your property is in safe hands. You can get in touch with our team by calling 0800 288 8660 or book a survey online.