In short
It can, but it is rare. Which? says cavity wall insulation usually only causes damp where a house faces severe wind-driven rain or the walls are poorly built or in very bad condition. Leaking gutters and roof edges often play a part too. A camera inspection of the cavity, and a look at what is wetting the wall, tells you which it is.
This is a job for our Cavity Wall Insulation Removal service.
When the insulation is to blame
Which? says that "in some rare cases, cavity wall insulation can cause damp problems", usually where a home is exposed to severe wind-driven rain, or where the walls are poorly constructed or in very bad condition. The idea of a cavity is that the gap stops water crossing from the outer wall to the inner one. If the insulation in that gap gets wet, it can carry damp across.
When something else is to blame
Which? also lists faulty guttering and roofing among the common causes of penetrating damp, along with water leaking from gutters and downpipes. It notes that a missing or defective cavity tray can cause penetrating damp too. As roofers, this is what we look at first:
- Gutters overflowing down the face of the wall.
- Leaking gutter joints and downpipes.
- A roof edge or flashing letting water into the top of the wall.
- Worn pointing above the damp patch.
If one of these is soaking the wall, taking the insulation out will not cure the damp on its own.
Check your guarantee first
Many cavity wall installations carry a guarantee from CIGA, the Cavity Insulation Guarantee Agency. CIGA says that if there is a problem, you should contact the installer named on the guarantee first, and that if the installer is no longer in business, CIGA itself will respond. You only need your address and postcode for CIGA to look up the guarantee. If it applies, remedial work for a defect is carried out under its terms, so it is worth checking before you pay anyone.
How we find out what is going on
- A camera goes into the cavity through a small opening, so we can see the insulation, any gaps or slumping, and any debris bridging the cavity.
- We check the gutters, downpipes, roof edge and pointing above the damp.
- We show you the footage and photos and explain what we think is happening.
- If the insulation has failed and is not covered by a guarantee, we quote in writing to remove it and fix whatever was wetting the wall.