100 year old house–insulation for exterior walls/ceiling
We’re gutting a 6×15 area, originally a pantry, to add a tiny powder room and walk thru pantry. The exterior sidewalls are 3/4″ pine boards with redwood clapboards. About 15 years ago we stripped the claps, used oil based primer and 2 coats of high quality latex paint. There is no housewrap, but some red rosin paper under the claps. The roof is sound with no leaks.
Above the space is an open-air porch with a very slight hip roof. The roof joists are 2×8’s. Using batt insulation for the roof will be a nuisance, and won’t meet code for Rvalue. We’d rather not drop a ceiling to add thicker batts.
The walls are full 2×4’s. We don’t have any moisture problems, rot, or mold.
Is this a good application for closed or open cell foam? Is one brand superior, or more cost-effective? Hubby is skilled at renovations (kitchen, garage, full bath, he’s done it all.) How much should we put in the ceiling? How much in the walls?
We’re in WIsconsin, and this space is on the north side of the house. It doesn’t get much sun. It’s exposed on all sides to the exterior.
Thanks for any/all advice!
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