TJI Joists to Masonry Firewall

[tmlim]

Without using a firecut, does anyone know of a way to connect TJI joists to a masonry firewall??

There will be joists on both sides. If the joists fail on one side, the other side still has to support the wall laterally. Obviously if the joists fail on one side, they also can't take down the wall as well.

Any ideas??

 

[Ron]

Why not masonry joist hangers, or am I missing something?

 

[tmlim]

Ron,

With joist hangers there are 2 situations:

1. If the Joist is fastened to the hanger, it will damage the wall if the joist comes down.

2. If the joist is NOT fastened to the hanger, the wall will not receive the lateral support.

 

[SkiisAndBikes]

tmlim,

Fire walls can be constructed using two independent masonry walls that abut one another. The TJI joists from one side frame onto only one of the masonry walls and vice versa for the other side. Fire in one compartment could result in collapse of one set of the TJI's and attached masonry wall, however, the fire separation of the other wall will remain intact.

You could also look at fire rated stud walls on each side of the masonry fire separation that would provide support for the TJI's, independent of the masonry fire wall.

There should be a ULC or Code approved detail for your area that details this situation.

 

[tmlim]

SkiisAndBikes,

Both good ideas that I have considered, but the bulk of the building design has been completed and construction of the foundation has started. So unfortunately, we can't add another masonry wall or stud wall.

 

[Ron]

tmlim...I understand, but Simpson has a rotation hanger that will allow the joist to rotate without transferring the rotation to the wall. It will still provide lateral support. Check with Simpson...I don't know the number of the hanger, I just ran across it several weeks ago when looking for something else.

 

[tmlim]

Ron,

I contacted Simpson and they don't have anything that will meet my criteria.

 

[DaveAtkins]

Perhaps you can use adhesive anchors to fasten a continuous steel support angle to the masonry wall. The adhesive fails at a low temperature during a fire.

DaveAtkins

 

[JLNJ]

I'm not a fan of the temperature "fusible link" type anchor theory. What if the fire is at the other end of the building and the temp near the end with the links never gets to the point of release before collapse? The falling building is then trying to pull everything over. It doesn't seem to meet the intent of the separation indicated in the code.

 

[ALazyStudent]

Bolt a ledger to masonry, embed some straps around masonry rebar. Nail straps to top of joist for out of plane connection, use a simpson hanger for TJI.

Is there some facet of the masonry firewall that I'm not catching onto that will prohibit this solution?