Looking for a modern approach to an uninsulated 1928 kit house
We’re in Westchester County, NY in a 1928, 1500 sq 2 story balloon-framed Bennett Homes kit house. Wall construction is original plaster/lath over nominal 2×4 covered by t&g cedar backer-boards, tar paper, and finished with cedar lap siding and paint. These original walls have been well preserved behind vinyl/eps that we plan to remove and then sand, patch, and paint.
The question is how to handle insulation. Do we insulate the walls with blown-in Rockwool, use vapor barrier paint inside, and tighten up the place….. or leave the walls empty. We’ve been hearing that the lack of a modern vapor barrier means that any insulation will tend to trap moisture that can be absorbed by the framing, creating conditions for mold, terminates, and possibly rot. Will a vapor barrier paint really prevent that? We’re installing an ERV but since we like to live with open windows 6 months a year I don’t think we can count on that.
Will hollow walls be a huge factor if we foam the sill and top plates, provide for respectable R values in the attic and replace the circa 80’s window inserts? We’ve been here one winter with radiators and while the thermal images show cold spots in the corners it didn’t feel drafty. Perhaps that will change dramatically when we replace the radiators and all the supply pipes that feed them with Mitsubishi Hyper Heat units.
There are many articles on these topics but haven’t found one that addresses all the issues in concert that we’ve been wrestling with and would appreciate your thoughts.
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