Floor truss fire rating
conwaynh85
| Posted in General Questions on
Hello smart people,
I have an 18″ open web floor truss assembly in a single family residnce. I had planned on it being left open to the unfinished basement, but my code enforcement advised me that it needs to be fire rated. I see an exception in the 2018 IRC for the material being the equivalent to a nominal 2×10. Has anyone run into a truss meeting that requirement or another exception. It would be awful to put up a drywall ceiling in a utility room that’s covered in pipes and wires.
Thank you for any advice or guidance.
https://codes.iccsafe.org/s/IRC2018/chapter-3-building-planning/IRC2018-Pt03-Ch03-SecR302.13
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Replies
Triforce Openjoists have gone through the requisite testing and can remain exposed, except for the OSB flange at one end. I'm not aware of any other wood trusses that have gone through the testing procedures to prove equivalence to a 2x10. If you have a fire sprinkler you could likely leave them exposed, but otherwise they need to be covered.
Michael, thanks for the response. After further investigation it appears that this is just a new normal. Good to know about triforce though, that may be useful when comparing future floor systems. Thanks again.
You're welcome. I found out the hard way as well.