I need to attach a few 4X4 wood posts to an existing roof deck with an EPDM membrane bonded directly to an OSB layer. The underlying roof deck combined with the OSB is substantial and lag-screwing some sort of post anchor plates to it would be plenty strong . . . but it would need to be water tight . . .
Is there a standard type of anchor plate or device that works well? Brand or description?
If I use a standard metal post base, can I get by with sealing it to the roof with some type of rubber caulk, or would I need to flash around each post with rubber? If so, is there a type of post base that is easy to flash?
Are there any tricks that work especially well, like building up a flashed-in raised block under each post to keep water away from the attachment point?
Thanks in advance!