Tag debates new model-language on anchorage of water heaters and seismic strapping

During review of Chapter 3 provisions, staff recommended repealing Washington’s prior amendment that referenced only water heaters and instead adopt the 2024 model-code approach that applies to appliances and equipment fixed in position. Staff noted the 2024 text expands the requirement beyond traditional water heaters to include other fixed appliances in seismic areas.

Committee members highlighted practical ramifications. The draft model provisions and staff commentary use a 400-pound installed-weight threshold and a 4-foot measurement for the bottom of the appliance above the floor as part of exceptions; committee members observed that a 40-gallon water heater (installed weight plus water) can exceed 400 pounds, and that a tall but lighter appliance could meet one exception but not another. Ken Brulette, Representative, Seattle City Fire Department, and others observed that Washington jurisdictions largely sit in seismic design category D (and some areas are moving toward E in the code cycle), which makes the strapping and anchorage rules especially relevant.

Multiple members asked for more review of how the new model language aligns with the Uniform Plumbing Code (UPC) anchorage section (UPC 507.2 / 402.5 references were discussed) and how the UPC and IRC cross-reference should be handled. Staff said the matter should be revisited in the significant-changes report and volunteers should compare the UPC text to the model-code revisions to ensure the rule will not inadvertently require strapping of non-fixed equipment.

Next steps: staff will bring the item back flagged for further cross-code analysis (UPC vs. IRC/model code), and the tag will examine the proposal in the significant-changes report before deciding whether to preserve part of the state amendment or adopt the model-code wording.