ICC Governmental Members Approve IIBEC Secondary Drainage Proposals

By Emily Lorenz

Results of the International Code Council’s (ICC’s) online governmental consensus vote—including the passage of both of IIBEC’s code change proposals (CCPs) submitted for the 2024 International Building Code (IBC) and International Residential Code (IRC)—were posted last week. This step finalizes results from the ICC’s Public Comment Hearings in Louisville, Kentucky, where IIBEC Senior Director of Technical Services Emily Lorenz, PE, was joined by IIBEC Secretary/Treasurer Chris Dawkins, PE, in defending IIBEC’s two CCPs related to minimum slope and secondary drainage during reroofing. Detailed information on the outcomes of the CCPs can be found here.

Reapproved: S-44

• This proposal adds a requirement to Exception 1 of Section 1512.1 of the IBC to check for ponding instability if an existing roof doesn’t meet minimum slope.
• Approved language (changes shown in underline):

Roof replacement or roof recover of existing low-slope roof coverings shall not be required to meet the minimum design slope requirement of / unit vertical in 12 units horizontal (2-percent slope) in Section 1507 for roofs that provide positive roof drainage and meet the requirements of Section 1608.3 and Section 1611.2.

Reapproved: S-45

• This proposal adds a requirement to Exception 2 of Section 1512.1 of the IBC to check for ponding instability if an existing roof doesn’t have secondary drainage.
• Approved language (changes shown in strike-through and underline):

Recovering or replacing an existing roof covering shall not be required to meet the requirement for secondary (emergency overflow) drains or scuppers in Section 1502.2 for roofs that provide for positive roof drainage and have been determined to resist all design loads meet the requirements of Section 1608.3 and Section 1611.2. For the purposes of this exception, existing secondary drainage or scupper systems required in accordance with this code shall not be removed unless they are replaced by secondary drains or scuppers designed and installed in accordance with Section 1502.2.