Hello,
A family room extension to our house has a vaulted ceiling. This is constructed from 150mm rafters with 100mm solid insulation between the rafters, leaving a 50mm void between the insulation and breathable roofing membrane. Insulated plasterboard has then been screwed to the rafters and skimmed, giving a nice catherdral style room. Apart from the breathable membrane there is no other ventilation to the 50mm void.
Cut into the plasterboard are six downlighters. My worry is that moisture will escape through the downlighters and condense in really cold weather on the underside of the membrane and over time soak into the timbers. My worry is further increased by the fact that I cannot inspect the void to see what is going on, without maybe removing the soffits and guttering and inspecting from the outside. Even if I fit soffit vents I still can't be sure there is no condensation.
Is there anything I can do? Or should I just not worry and maybe let it rot!
Thanks,
Graham