Floor Trusses With Masonry Bearing Walls
Question:
We would like to know if there is a problem with using wood floor trusses with masonry bearing walls without a ledger. Our local supplier has told me that encasing the wood truss in the masonry wall could be detrimental to the truss due to moisture. What, if any, suggestions do you have for this condition? If a bottom chord bearing is used, do the trusses need fire cuts? The two-story building contains masonry bearing walls with wood trusses on the second floor and wood trusses at the roof.
Answer:
You can use wood floor trusses with masonry bearing walls without a ledger. We suggest that you use a bucket hanger that can be encased in the masonry wall and used as bottom chord bearing for the floor truss. A detail of this can be found on SBCA website. If you still wish for the bearing of the truss to be on masonry, the truss should be fire cut to allow it to rotate out of the wall if it burns through. The truss must also be anchored against pulling away from the wall, either with lag screws or a lug on the iron bearing wall. The connectors that you would need are available through any connectors catalog.