Sealing Brick Veneer…or not?
I have a modular masonry fireplace. The chimney has a brick veneer with a small gap between the brick and the masonry blocks. I initially had a small leak through the brick and onto the chimney’s built-in brick ledge (in the attic) during a rain. This seems to have stopped based on observation during subsequent rains. It has been recommended that I spray the chimney brick with a sealer.
1) Do I need to do this? Why did it leak at first and now it doesn’t? The mortar wasn’t fully cured at the time of the initial leakage—would that make a difference?
2) Separate, but related issue—–My painter suggested that I spray a sealer on the brick veneer of the entire house to seal it off and save the white mortar from discoloring over time. Would eliminating the permeability of the brick (on the walls of the house) create drying problems to the outside, or is the air gap sufficient to handle any moisture load seeking to escape to the exterior? I’ve read EEBA literature suggesting that painting brick is a bad idea (for lots of reasons). Spraying on a sealer seems to be akin to painting the brick.
HH climate —zone 2B. 2×6 walls, plywood exterior sheathing, 1″ gap, brick veneer, oc spf insulation, non-vented attic.
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