I Joist Used As Roof Rafters

Shall be permitted to be used.

I joist used as roof rafters.

Because i joists are straight and true it s easier for builders to avoid crowning and maintain a level framing surface. No solid sawn conventional lumber should be used as rim joist with i joist. For hip roofs with the hip trusses running parallel to the cantilevered floor joists the i joist reinforcement requirements for a span of 26 ft. It is always better to have a large rafter rather than be concerned with a sagging roof.

Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. Trus joist tji s31 s33 and s47 joists for use in eastern canada. Again put them closer together if you want to achieve a greater span. Looks like they can be used as rafters.

These i joist rafters are on 24 inch 61 cm centers and support plywood roof sheathing and wood shingles. An spf rafter can span nearly 15 at the same dimensions. Software weyerhaeuser offers an array of software packages to help you specify individual framing members create cut lists manage inventories even to help you design a complete structural frame. Photo 2 shows a view of the other ends of these same i joist rafters and the use of.

Use 2 6 rafters if your roof will experience heavy snow or wind loads. Bci joists are specially constructed i joists with flanges made from strong versa lam laminated veneer lumber with oriented stranded board webs and approved waterproof structural adhesives providing outstanding strength and durability. Can span over 18 for gable roofed shed. Syp 2 6 rafters at 24 o c.

Insulation should be 1 inch from b vent. There s no reason to used i joist with a 15 span. 6 8 sloped bearing conditions. All you need is 22 2x10 s or 2x12 s.

Just found this interesting. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. Should not be cut like near the b vent. With an 8 soffit your rafter without a ridge deduction is roughly 20 4 3 4.

I joists make for a strong flat roof but you have to pay attention to the connections at the ridge and eaves. They are ideal for long spans including continuous spans over intermediate supports. 2 0 maximum cantilever roof truss span 2 0 maximum cantilever hip girder trusses truss roof trusses 13 0 maximum roof truss span.