How to brace a truss roof without OSB or plywood?
rocketconstruction
| Posted in Green Building Techniques on
We are putting up a cathedral roof structure made with engineered trusses, however we are putting a metal roof on it. I would like to avoid using sheething and would prefer to use vertical 2×4 channel for ventilation with furrings on top to screw the roof to. Are the furrings and metal roof enough for bracing? Can metal T braces be used?
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Replies
William if the trusses were made by a company using Mitek's software there is a spot on the drawing that specifies minimum bracing. On my trusses it specifically calls out sheathing the top chords and bottom and a few straight braces. Their installation instructions also show lots of diagonal bracing near the ends, every 10', and above the bottom chords.
I is also going to be very difficult working up there with no support except a truss.
William,
The short answer is that you should consult an engineer.
You can brace the underside of your roof trusses with diagonal 2x4s nailed to the underside of the top chords. Moreover, most brands of metal roofing are wide enough to help brace the roof. But really, only an engineer can answer your question.
William,
As Mike said, the minimum bracing requirements are shown on the shop drawings that came with your trusses. The only way you can deviate from them is with the approval of the manufacturer's engineer. Unfortunately, you stood a lot better chance of using just strapping if you had told them in advance so they could modify the design.