Sealing & Insulating Asphault/Felt Impregnated Fiberboard
I am in the planning phase of renovating a single story house built in 1958. Removing the inside wall paneling, we found that the sheathing was asphalt/felt impregnated fiberboard (no insulation in the wall cavity). We want to insulate the walls before putting on dry wall, but are not sure how to do so correctly. Removing siding or sheathing is not an option for financial reasons, so we’re hoping someone can give us insights how to seal/insulate the interior cavity knowing we’re dealing with asphault/felt impregnated fiberboard.
FYI the outside siding is wooden board and batten, they put some type of exterior house wrap, and the sheathing is obviously the fiber board which is connected to 2×4″ studs.
Help please!
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Replies
If you have house wrap on the outside, you can insulate with standard batts. I would check around window and openings for sign of water leaks. Those must be fixed otherwise you end up with a moldy mess down the road.
Air sealing fiberboard is impossible without spray foam. The low cost air barrier would be your drywall. Make sure to install vapor tight device boxes with a gasketed flange as these leak much less than standard units.