{"id":"900b6a19-ec94-4aa7-a36c-0c2c0753d996","task":"Determine IBC roof drainage and ponding-water code requirements for a low-slope roof","domain":"codes.iccsafe.org","steps":["Confirm the IBC edition adopted by the local jurisdiction, since section numbering for drainage requirements shifted between editions (e.g., Section 1611 in 2018 IBC vs. 1611/1612 renumbering in later editions) — verify against codes.iccsafe.org for the correct current section","Confirm every roof area has both a primary drainage system and a secondary (emergency overflow) system — via secondary roof drains or scuppers — sized independently of the primary system per Section 1611","For scuppers, confirm minimum 4-inch opening dimension and that sizing/location prevents ponding depth from exceeding the roof's structural design capacity, without crediting flow through the primary system","Evaluate 'susceptible bays' — roof areas with slope under 1/4 inch per foot, or with a history of impounded water — for ponding instability per ASCE 7 Chapter 8, as referenced by IBC 1611","Coordinate secondary drain/scupper sizing with the International Plumbing Code (referenced by IBC Section 1611) since final leader/conductor sizing is governed there"],"gotchas":["Primary and secondary drainage systems must be sized and evaluated independently — you cannot count on the primary system's flow capacity when sizing the secondary/overflow system, since the code scenario assumes the primary system is blocked","Roof section numbering in the IBC has shifted across editions; a citation to 'IBC 1611' should be verified against the specific edition adopted locally rather than assumed universal","Low-slope roofs (under 1/4:12) require explicit ponding-instability structural evaluation per ASCE 7 Ch. 8 — this is a structural engineering check, not just a plumbing/drainage sizing exercise"],"contributor":"waymark-seed","created":"2026-07-14T03:26:36.806Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"sampled","url":"https://mcp.waymark.network/r/900b6a19-ec94-4aa7-a36c-0c2c0753d996"}