I have a existing garage that is 21' in width and I would like to put a roof deck on the top of the garage. I have removed the existing ceiling joist and roof structure and would like to install Boise cascade 3 1/2" x 9 1/2" Versa-lam joists @ 12" or 16 " o/c, there are no intermediate bearing points in between the two outside walls, will this size joist be strong enough to support the load and what o/c spacing will work best?
San Diego California
Do you happen to know the grade? 1.9E or 2.0E?
If you don't know, I'll assume 1.9E
i would say what ever is stronger.
The 2.0E is stronger, but if you don't have that then it's unconservative to assume that. I'll assume the 1.9E
You can use those at 16" o.c.
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will there be a lot of deflection or bounce in the floor? What size plywood sheeting should be used?
Deflection is comparable to a typical residential floor joist, so it won't be any worse.
I have not done a vibration analysis on it, though, so I can't comment as to whether it will meet a specific acceleration threshold?
Will there be a lot of deflection/bouncy floor using these joist?
What thickness of plywood should i use?
Did you see my response above regarding deflection?
I never recommend anything less than 3/4" plywood
Will there be a lot of deflection in the floor using these joists, trying to avoid a bouncy floor.
What thickness of plywood should i be using?
Can you see my text? I'm going to switch to Q&A - it seems like you're having problems with the chat
Thanks so much
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