I've built a timber framed extension to my mobile home (UK if it makes a difference). I Boarded up the walls and wrapped them with Cromar vent 3 felt, and cladded over the top with pvc cladding. Inside I started to insulate between the studs with knauff earthwool and after a few days checked to find moisture behind almost every slab (worse nearer window). I have since removed the earthwool and celotex from the ceiling, put in a heater and dehumidifier to dry the room. I think the window may have been open very slightly, and the room was sealed independent from the rest of the home, leaving it very cold. Since then I've opened up a doorway to the rest of the home, the window seems completely closed (2nd hand window, slight problem with hinge I think), and everything is dry. Should I put the insulation back up, or use something like Ronseal condensation paint on the boards beforehand? I'm concerned that if I put plasterboard on top before fixing any issues I'll have a damp problem. Thanks in advance. via /r/DIY http://bit.ly/2siprBz
