Is special preparation required for enclosing a former doorway behind a masonry wall?
Hello.
We removed a door that used to provide access to our house from the garage. On the interior side of that wall, we used two layers of fire-rated drywall and insulated with dense-packed cellulose. On the garage side of the wall, there’s a door-shaped empty frame in the masonry wall. I have a few questions about how we should brick up that doorway. [I attached some pictures.]
1. When we brick up the doorway, could off-gassing from the mortar cause potential moisture issues for the drywall? Do I need to treat the drywall before we brick in the opening?
2. On the garage-side of the wall, should we seal the seams between the drywall and 2x4s before doing the masonry?
3. Should the new masonry to brick in the doorway be ‘toothed’ to match the rest of wall? I understand that the toothed version will be stronger, but to what extent is that relevant in this context?
I’ll appreciate any guidance you can provide.
jp
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Replies
Patrick,
1 & 3, It seems like a lot of work for little return to fill in the wall with masonry. I'd consider making a shelving unit on the garage side to fill the space, or just furr out the wall flush and drywall the opening. If you do decide to go with blocks, the only reason to 'tooth" it would be for looks.
2. definitely seal the opening to stop any fumes entering the house.
Thanks for the response, Malcolm.
I did the best I could insulating the walls, but they are built with 2x4s, and the garage isn't heated, so I want to fill in the opening. Do you know whether off-gassing from the mortar could lead to moisture issues with the drywall?
jp,
The mortar will be fine. Filling the opening with masonry will however do nothing to stop heat loss from the garage.
Right. Since the garage isn't heated, it's colder in the garage than in the house; in fact, recently it's been colder in the garage than outside. So, re-bricking the garage wall is to help keep the garage's cooler/warmer air from affecting the interior of the house. The R-value of masonry is minimal, but with 2x4 interior walls, I'll take any help I can get.
Anneville,
You will get less than R-2 from the block. That's the same as a 1/2" layer of foam. If you framed another wall in the opening you could easily get another R-20. Or you could put 2" of EPS (R-8) and still have room for shelves.
Thanks for the ideas, Malcolm.