Does anyone have any experience or thoughts regarding caulking the cracks in the ceiling -- Not the natural v-shaped groove that exists between adjoining tongue & groove boards, but the deeper cracks that appear behind those. They have become more pronounced as the wood dries and shrinks over the years. A painter recommended this process using a paintable 30 or 50 year caulk formula – I tried it on a few boards and it eliminates the dark lines that can sometimes be unsightly. Are these cracks necessary for the roofs “breathing”? Is there some long tern effect?
I recently purchased an Eichler-like house in Spokane, WA, whose bathroom ceiling gaps (2x6 painted redwood t&g) had all been caulked. I don't know when this was implemented, but now it is brittle, cracking and bits are starting to fall out. The material used was probably not as good as current available products.
In any event, even with this bathroom caulking, the waferboard (or whatever that soft, wood composite product is they used to insulate in the 50's) above the bathroom is VERY wet. No one has lived in this house for 2 years. The roofing materials away from this bathroom are not wet. The plywood above this "insulation" is not degraded. The moisture definitely entered from below, and stayed put.
Beyond installing a ceiling fan, I am presently trying to decide how to reroof to avoid the moisture build-up under the roof. T&G, Ice & Snow moisture barrier, PolyIso insulation, then topped with some solid surface membrane? Should there be some escape for moisture at the eaves? Any suggestions are very welcome! No roofers in this part of the country seem to know the answer.