Why is my brick home still standing?
Thanks to all who have contributed to the volume of resources discussing brick and masonry wall and foundation insulation. It seems the prevailing approach is cc foam on masonry, but not too much on the brick walls.
I’m renovating a 1890 brick home. We are in MT, zone 6B, 12″ annual moisture and cold dry winters. The brick walls are all above grade, double wythe with 2″ air space. Crawl space walls are all above grade and the full basement walls are mostly below. I’m considering insulating some of the brick walls and will be required to insulate the rubble foundation. My primary concern is trapping moisture in the masonry that will rot the embedded joists and sill plates by applying CC foam. I could be wrong, but I assume that moisture will always find a way. Isn’t it best to maintain some drying and inspection ability?
The “still standing?” question is actually facetious and about my current home which I’m comparing as I work on the renovation. It is brick wall and rubble foundation construction from the same era, no brick insulation, R50 celluose in the attic under a simple vented gable roof. The floor joist on the foundation have some batt insulation and the 2×4 wood framed addition has fiberglass batts. When it is cold we get freezing condensation on the double pane windows and when colder the north brick walls also get condensation. So I have pulled electrical boxes in the addition to inspect sheathing and looked at the floor and roof joists where they contact the masonry. They all look great. I understand the situations are different, but given my comparisons would you also be cautious about applying a vapor impermeable insulation in the renovation?
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