A. John Leeke, a preservation consultant from Portland, Maine, responds: The first step is to investigate the masonry to determine what type of bricks and mortar was used. Repressed bricks that are very square, with even sharp edges, and laid with narrow mortar joints, are usually fired hard and intended to hold up to the weather on their own. Some buildings were made of softer bricks with rounded edges; these softer brick were intended by the original builders to be painted. You wouldn’t want to leave this type of brickwork exposed with no paint, because the surface would absorb too much water, causing serious problems over the long term.
If the bricks need a coating, determine if the existing coating is still performing its intended function. If the bricks will have to be recoated for the good of the building, the owners will want to reconsider their decision to expose the bricks.
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