Airsealing an attic
Hello, I have a 172 year old brick home and have some questions regarding attic venting. My attic is in poor shape. It was “finished” when the house was built, with plaster walls, a flat plaster ceiling and 1 partition wall. I’ve been in the house about a year and am just now deciding to do some work up there. There are sections of sagging plaster and a few holes in the ceiling. I decided to widen a hole in the ceiling to peek up into the very top of the roof. The timbers look like they’re in great shape but the masonry at the gable ends and chimney stacks are crumbling. In one spot there are bricks missing from the chimney and I can reach right in and touch the chimney liner connected to my woodstove 2 stories below. Also, many many wasp nests which explain their presence in the house. So technically with all the voids, the attic is kind of “vented”. I’m wondering if the roof timbers are dry and intact because of this. I’m afraid that if I repoint/repair the masonry, and possibly spray foam any random voids I find, I’ll be sealing the attic, eliminating fresh air movement and possibly trapping moisture there. By the way the roof is original cedar shakes directly on the rafters, with metal panels having been put on top probably some 100 years ago. I hope I explained everything correctly, if not please ask/tell me. Looking forward to some advice, thank you.
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