Revisions log for Answer #3180
This is the answer to the question Why is the brick crumbling around the air ducts on the facade?
Revision 1
I would do a thorough revision of the apron around the pipe – water from the roof should not get on the brick, neither in summer nor in the off-season, when the snow does not let it escape and its level rises.
Revision involves checking the compliance of the executed / actual to what is intended. In this case, compliance with the junction of any typical solution – they are the same in all manufacturers of roofing materials. I think that the brickwork in your case suffers the least from condensation, the greatest from rain and melted snow. From the top cap, water is likely to run down the surface of the masonry, and the brick naturally soaks it up. The surface of masonry can be protected by coating waterproofing it, but you need to know the temperature (limit) of heating. Almost all compositions are vapor permeable.