Can cavity wall insulation cause damp problems?

The purpose of cavity wall insulation is to prevent heat from escaping your home, keeping it warmer in the winter and lowering your heating bills. Although it’s great for improving the energy efficiency of your house, there is a risk you need to watch out for: damp. If your cavity wall insulation is infected, damp can spread into your internal walls, causing structural damage, stains, peeling wallpaper, and mould.

Croft are specialists in the detection and treatment of damp problems. In this post, we explain why damp can form on cavity wall insulation, how to spot it, and what you can do to deal with it.

What causes damp in cavity wall insulation?

Damp in cavity wall insulation is usually caused by one of two things:

• Poor installation: When installing cavity wall insulation, the installer should leave room for rainwater to drain within the cavity. If they don’t, the insulation can act as a bridge for water to travel from the outer to inner wall, eventually leading to damp. Gaps in the insulation can also lead to cold spots on the internal walls; when touched by warm air, these cold spots can be infected with damp.
• Unsuitable building type: Some cavity walls are not suitable for being fitted with insulation. Many have unfilled mortar joints and debris within, which can prevent the insulation from filling the cavity evenly. Houses in areas with a lot of wind driven rain (such as Wales, Cornwall, Somerset, and Devon) are particularly at risk of cavity wall insulation damp, as the high amount of water can saturate the outer wall and spread damp inside.

How do I tell if my cavity wall insulation has damp?

Because it’s out of sight, damp in cavity wall insulation is often hard to spot until it has spread to the inner wall. Warning signs include stains on your walls, cold patches, and a musty smell in your home.

If you suspect you have damp in your walls, it’s best to get it surveyed by a professional. They will have the tools and expertise needed to detect moisture deep within your walls, giving you a much better idea of the extent of your damp problem.

How do I treat damp in my cavity wall insulation?

Because it is deep within your wall, damp in your cavity wall insulation must be dealt with by an expert.

They will normally do this by removing bricks, disposing of infected insulation, and injecting new insulation. The exact method of treatment depends on your specific problem and the severity of the infection, as well as the condition of your wall.

Get help from the damp experts

The team at Croft have dealt with hundreds of damp problems across Dorset and Hampshire. We have nearly 40 years of experience treating damp in cavity wall insulation, from minor cases to severe infestations.

When we survey your property, we will carefully inspect your walls for signs of damp and mould. We will draw up a detailed report of all of our findings, as well as a competitively-priced quote for our services.

If you’re happy to go ahead, we will get to work eliminating damp within your cavity walls. We will take steps to ensure all infected insulation is removed or replaced, fix problems with your cavity wall ties, and replace your damp proof course if needed.

The end result will be a clean, damp-free home that’s safe for you and your loved ones to live in.

Book a survey online or call us on 01202 737739!