ASPE’s Main Design Standards Committee and Working Group 45 have reviewed the comments received during the first comment period for the revision to ASPE/ANSI 45-2018: Siphonic Roof Drainage, and the substantive changes resulting from that review are now available for public comment.

The ASPE 45 system design standard applies to engineered siphonic roof drainage systems intended to prime and operate full bore through proper pipe dimensioning and the use of siphonic roof drains. It establishes minimum performance specifications for systems, provides guidelines for inspection and testing, and describes the basis for the design of siphonic roof drain systems. This standard does not apply to conventional roof drains covered under ASTM A112.6.4/CSA B79.4: Roof, Deck, and Balcony Drains, atmospheric roof drainage systems, or sanitary drainage systems.

Directly and materially affected interests wishing to comment on the substantive changes are requested to do so by April 28, 2025.

To obtain a copy of the standard and the comment form, please contact ASPE’s Director of Communications, Marketing & Publications, Gretchen Pienta, at gpienta@aspe.org.

A notice of this public review was published in the March 14, 2025, edition of ANSI Standards Action.