RE: What is acceptable for SWR
My understanding is that to qualify for the credit there must be a self-adhering polymer modified bitumen membrane (“peel and stick”) to all deck seams or over the entire roof deck. Easy to identify because it must be sticky on the back side.
Does the following method qualify:
Install a high tear strength synthetic underlayment with all vertical and horizontal seams taped. The underlayment relies on nails with one inch caps to secure it to the roof deck (it is not sticky on the back when probed from the underside of the roof at a roof deck seam). Edges are over lapped 2 inches on the horizontal and 6 inches vertical then taped with 4 inch tape.