ASME A112.6.4

The ASME Standard is the National consensus standard for these products. This standard is referenced by Plumbing Codes.

The ASME Standard establishes minimum design requirements for roof drains, including general purpose, gutter and cornice, parapet and promenade, balcony, or deck types, which convey rainwater from the roof area of building structures. It includes definitions, nomenclature, outlet types and connections, dome or grate-free area, top loading classifications, materials and finishes, and accessories.

A roof drain is a plumbing fitting that is designed for installation in any roof area excluding the parapet of the roof structure. It is comprised of a drain body (sump), dome strainer, and gravel guard/membrane clamp. Optional components shall include under-deck clamp-standard, under-deck clamp-plywood substrate, expansion joint, and sump basket.

There are many variations on the basic Roof drain:

• Roof Drain with Overflow and Flashing Flange: The combination roof drain, overflow sump, and flashing flange with a dome strainer and gravel guard in one integral watertight unit is designed for flat roof construction and where independent overflow drainage is required. An optional feature includes a side outlet for special use in shallow joist areas.
• Gutter or Cornice Roof Drain: A roof drain for installation in gutters, cornices, balconies, and other overhanging construction to prevent overflow to areas below.
• Parapet Roof Drain: A roof drain for installation in parapets for conveying rainwater from a roof area through the parapet.
• Roof Parapet Drain with Flashing Flange: A roof drain with flashing flange for use in mansard or parapet roofs.
• Roof Drain with Overflow: A roof drain with integral flashing flange and overflow combination for use with mansard or parapet roofs where independent overflow drainage is required.
• Promenade or Deck Roof Drain: A deck drain is a manufactured receptor for installation in roof decks subject to pedestrian or vehicular traffic and that is fitted with a flat grate.