# Metal alternative for 2x4 truss rat runs when penetrating 1 hour fire wall



## RPM001 (Oct 27, 2020)

I have 2x4 permanent truss bracing at the bottom chord (rat runs) that penetrate 1hour drywall tenant separation walls (and the inspector won't pass it with wood penetrating). Has anyone ever used any type of steel/ metal beams instead of 2x4s in certain areas?  Or has anyone every built a metal sleeve to encapsulate the rat runs where they penetrate 1 hour separation walls?


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## steveray (Oct 27, 2020)

I believe that simpson makes metal "installation braces" but I am not sure if they are prescriptive for permanent bracing...Engineer?


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## mtlogcabin (Oct 27, 2020)

You should not need the bottom chord bracing (rat runs) with sheet rock installed on the ceiling. Check with the truss engineer. You should be able to remove it where the tenant separation walls are.


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## Paul Sweet (Oct 28, 2020)

Some of the web members look long enough to need lateral bracing.  It could be broken at the tenant separation walls as long as there diagonal bracing is provided in each unit to prevent racking. 

It might be worthwhile to see if the inspector would accept fire-retardant treated wood for the penetrating bracing.


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