Wet window cill boards

peter_pumpkineater

Hi,

I have a wet spot on the window cill, which keeps reapperaing for 2 months when I dry with a hot air fan. gets wetter every day. Its a cold room, window normally open at night, but even when its closed it makes no difference. that spot spreads from 1 side to the center. After having problems with the roof, I thought its seeping through the wall and I expected to find a puddle underneath the boards, but the concrete is all dry, so must be condensation? I cant feel a draft when the window is closed. What can I do to prevent that? Felt underneath? Probably not…

would appreciate some advice! Thanks!