• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

UL design number of a demising wall adjoining a shower


Registered User
May 20, 2023
What's the UL listing of a demising wall that shall have a two-hour fire rating but also adjoins a shower?
Is there a specific UL listing for this type of wall (Cement board+tiling), instead of the two layers of MR boards?
Build and apply covering per the UL listed wall, then install the shower. I have not seen a 2 hour listed premade shower or tub
Last edited:
I found this in the UL Directory Product IQ. I think this option could work for City's approval.
Link and attachment below in case you need it in the future.
Thanks for the advice.



  • BXUV.U443 - Fire-resistance Ratings - ANSI_UL 263 _ UL Product iQ.pdf
    187 KB · Views: 8
Please see below
1-Non-bearing wall
2-No specific STC rating required
3-It's located between two apartments
4-The shower stall is on one side only
The only unknown is where the cement board joins the drywall. The joint compound needs to be compatible with both. Perhaps a 1/4” gap filled with intumescent caulk is a good idea.
Last edited: