I have a "bar room" inside my shop. For the ceiling/loft above I used I-joist. It is a 20' span and they're 12" oc. I found 48' I-joist for $10 each so I couldn't turn them down. I cut short pieces of I joist on each end to brace them from side to side. I will have 3/4 tongue and groove OSB on the loft above the room or top side of the I-joist. I am unsure what I will have on the ceiling of the bar room or bottom side of the I joist, but it will probably be something fairly rigid. Do I need to put bracing between the I-joist in the middle or if I screw down all the OSB will that be enough?
I-Joist bracing
- Thread starter alex2929
- Start date
Firebrick43
Well-known member
A floor without bracing will have more spring to it and less stiff than one without. Many are quite acceptable without braces but that is more a function of depth (which you don't mention). It never hurts to brace. If you end up using steel liner or other stiff material as the ceiling it will serve the same function.
Best thing to do is check with the manufacturer of the I-joints.
I reserched it a while back and with a 14" I-joist and a 26 foot span they did not require blocking or crossbracing. I was surprised! I would thing it couldn't hurt and the floor would be noticable stiffer.
I reserched it a while back and with a 14" I-joist and a 26 foot span they did not require blocking or crossbracing. I was surprised! I would thing it couldn't hurt and the floor would be noticable stiffer.
oldcarpenter
Well-known member
Check manufactures specs. More than likely need “squash” blocks at bearing points. Doubtful midspan nracing is needed
rburke65
Well-known member
No idea on the bracing, but my thinking would be if they were designed to span 48’, and your spaning only 20’ and they are spaced over 12”…..I’m thinking you’re golden.
jack stand
Well-known member
I'm "with" oldcarpenter above.
Go online for the critical details. I know McMillan and others are online. Look for some identifying printing as to the manufacturer and possibly the joist series although I think the same principles apply to all of them.
The "squash blocks" at the bearing points are basically a odd thickness osb. The same as the normally used "rim board" that is part of this floor "system".
You've earned an official "you ****" with these $10 tji's
Go online for the critical details. I know McMillan and others are online. Look for some identifying printing as to the manufacturer and possibly the joist series although I think the same principles apply to all of them.
The "squash blocks" at the bearing points are basically a odd thickness osb. The same as the normally used "rim board" that is part of this floor "system".
You've earned an official "you ****" with these $10 tji's
duneslider
Well-known member
No need for blocking in the mid-spans on I-joists. If I remember right I haven't read that in any of the I-joist manufacturers spec books. With osb glued and nailed down it is all you need. I have heard some people say they do it and it can help with vibration. Not sure if it helps or not as I haven't tried and I generally spec my floors out at L720 or better and don't have much of a vibration issue with that spec.
The Tool Tyrant
ALLIANCE MEMBER
As others have stated, check with the specific manufacturer as they MAY vary.
As long as both edges are held inline (ply on top and sheetrock etc on the bottom), there is no chance for overturning. Mid span blocking can potentially lead to squeaking, especially in long spans due to the nails moving in and out as the joist move up & down with foot traffic.
As long as both edges are held inline (ply on top and sheetrock etc on the bottom), there is no chance for overturning. Mid span blocking can potentially lead to squeaking, especially in long spans due to the nails moving in and out as the joist move up & down with foot traffic.