IIBEC Secondary Drainage Proposals Clear Next Code Hurdle

By Emily Lorenz

At the International Code Council’s (ICC’s) Public Comment Hearings in Louisville, Kentucky, September 14–18, 2022, Emily Lorenz was joined by IIBEC Secretary/Treasurer Chris Dawkins in defending IIBEC’s code change proposals (CCPs) submitted for the 2024 International Building Code (IBC) and International Residential Code (IRC). The purpose of the hearings, was to reaffirm or overturn decisions made by the committee during the hearings held in March of this year. The National Roofing Contractors Association submitted public comments disapproving IIBEC’s two CCPs related to minimum slope and secondary drainage during reroofing. However, with the support of the American Society of Civil Engineers Structural Engineering Institute, Lorenz and Dawkins successfully maintained the approval of these two CCPs.

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.

Disapproved: RB-257

• This proposal adds a slope requirement for various horizontal surfaces into the IBC. The section number of the change was revised, the language clarified, and it was resubmitted as a public comment, but opponents still felt the language was unclear.
• Submitted language (changes shown in strike-through and underline):

R507.11 Drainage of weather-exposed areas. Where the surface of balconies, decks, landings, porches, stairways, and similar surfaces exposed to the weather, and do not have spaces nor gaps or are not perforated to drain, they shall be sloped to drain.

Disapproved: S-3

• This proposal adds a slope requirement for various horizontal surfaces into the IBC. The section number of the change was revised, the language clarified, and it was resubmitted as a public comment, but opponents still felt the language was unclear.
• Submitted language (changes shown in strike-thru and underline):

1410 Drainage of weather-exposed areas. Where the surface of balconies, decks, landings, porches, stairways, and similar surfaces exposed to the weather, and do not have spaces nor gaps or are not perforated to drain, they shall be sloped to drain.

All approved and disapproved proposals now go to ballot through the ICC’s online governmental consensus vote (OGCV), which is expected to open in early October 2022. Results of the OGCV will set the final proposals that will appear in the 2024 codes. These results are expected in late October 2022.