Installing new DWV system, finally ready to cut the stack through the roof. The flashing/boot that I bought says "do not caulk". I assume that means don't use caulk around the neoprene gasket that seals around the stack pipe, makes sense to me.
But what about the flat underside of the aluminum flashing itself? I would think that a bead of sealant around the perimeter would make sense, so no rain rolls under it and into the hole in the roof. Any thoughts?