By IIBEC Senior Director of Technical Services Emily Lorenz
IIBEC member Stephen Patterson, coauthor of Roofing Design and Practice, and IIBEC Senior Director of Technical Services Emily Lorenz represented IIBEC member interests at the International Code Council’s hearings in Las Vegas, NV, that occurred October 23-30, 2019. Their primary testimony was focused on removing Exception 2 from section 1511.1 of the 2021 International Building Code (IBC) and section 705.1 of the 2021 International Residential Code (IRC). The IBC exception states:
Re-covering or replacing an existing roof covering shall not be required to meet the requirement for secondary (emergency overflow) drains or scuppers in Section 1503.4 for roofs that provide for positive roof drainage. 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 1503.4.
Exception 2 was added during development of the 2015 IBC and IRC and is also included in the 2018 IBC and IRC. This exception allows omission of secondary drainage during a roof replacement or re-covering. IIBEC members have expressed concern that roofs without secondary drainage are more prone to collapse due to water accumulation, which creates a life-safety issue. An IIBEC Technical Advisory was issued in 2017 due to the addition of this exception to the code. In addition to citing potential collapse concerns, Patterson and Lorenz also argued that code provisions are meant to establish minimum requirements to ensure life safety, and that this exception goes against long-established industry best practice to provide secondary roof drainage, as evidenced by the codes prior to 2015.
Exception 2 was originally introduced into the 2015 IBC by the National Roofing Contractors Association and representatives from NRCA, the National Association of Home Builders, and the Roof Coatings Manufacturers Association were present to argue for keeping the exception in the 2021 IBC.
IIBEC representatives failed to successfully argue to remove the exception; thus, this life-safety issue will remain in the 2021 IBC. Per IIBEC’s Technical Advisory, “Where the 2015 IBC and/or 2015 IRC [and/or 2018 IBC or IRC] are not yet adopted by the state or local jurisdiction, the code council in that state or jurisdiction should be notified to inform them of the risk these exceptions represent.” IIBEC members are encouraged to contact local code officials to advocate against adopting this change locally.