Weyerhaeuser had long been the lone I-joist manufacture specifically listed in UL® fire assemblies. In October 2016 we made the decision to no longer use UL as a listing service for our fire-resistance rated floor/ceiling assemblies. This move aligns us with the rest of the industry and will hopefully simplify the fire rated assembly options available.
The previously UL assemblies held by Trus Joist now have a generic I joist specification and can be found on UL directory searches.
Additional means to specify fire rated assemblies are as follows:
- Generic code-prescribed assembly (IBC Section 721)
- IBC Table 721.1(3) or American Wood Council DCA 3
- Gypsum Association Manual (See IBC 721.1(3) footnote q)
- Component Additive Method (IBC 722.6, American Wood Council DCA 4)
- Engineering analysis of similar assemblies based on testing