Installing rigid foam insulating board on the interior of an exterior wall
1890 house we’ve pulled the plaster and lathes off. Have access to exposed exterior wall between studs from the inside. Can we cut and tightly fit 2″ board between the studs, Should it be snug to the exterior wall? Or will there be a moisture issue…how do we prevent moisture issues? If we double layer the board does it increase effintiency? do we need to tape the seams against the studs? We live in Maine.
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What do you see on the exterior wall? Is it wide-plank sheathing, or clapboard siding nailed directly to the studs, or something else?
wide plank. The studs are 16" on center there are shingles on the outside of the wide plank.
Andrea,
The insulation method you propose to use is called the "cut-and-cobble" method. For more information on this topic, see Cut-and-Cobble Insulation.