In June, the ASME/CSA Committee met in Halifax, Nova Scotia, Canada to review the various A112 plumbing-fixture standards. One of the meetings held was on the roof drain standard. During that meeting, the never-ending dilemma regarding roof drain design arose.
The dilemma relates to the structural engineers’ approach to addressing roof loads based on the plumbing engineers’ design. Since the 1990s, structural engineers have had more to say about roof drainage than the plumbing engineers. What I mean by that is the structural loading is dictating the type of roof drainage design allowed for a building.