Condensation trapped behind closed cell foam
Why it happens here
Closed cell foam is impermeable, so any moisture in the roof space cannot escape. In West Hoe, sea air and driving rain add extra moisture. When the foam was sprayed without a ventilation gap, condensation builds up on the cold side and soaks into timber.
Our approach
We remove the foam completely, then clear and improve ventilation so the roof can breathe. We check timber moisture levels before and after, and treat any early decay. This stops the problem returning rather than just removing the foam.