I Joist Used As Roof Rafters
Looks like they can be used as rafters.
I joist used as roof rafters. All you need is 22 2x10 s or 2x12 s. Syp 2 6 rafters at 24 o c. Use 2 6 rafters if your roof will experience heavy snow or wind loads. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.
Trus joist tji s31 s33 and s47 joists for use in eastern canada. With an 8 soffit your rafter without a ridge deduction is roughly 20 4 3 4. I joists are used extensively in residential floor and roof framing. 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.
6 8 sloped bearing conditions. When wood i joists are used as rafters connections at the structural ridge and the tops of exterior walls must be detailed properly. There s no reason to used i joist with a 15 span. 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.
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. They are ideal for long spans including continuous spans over intermediate supports. Should not be cut like near the b vent. 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. Insulation should be 1 inch from b vent. Because i joists are straight and true it s easier for builders to avoid crowning and maintain a level framing surface. Pdf says to consult with specific manufacturer for design installation specs.
Again put them closer together if you want to achieve a greater span. Can span over 18 for gable roofed shed. Shall be permitted to be used. 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. No solid sawn conventional lumber should be used as rim joist with i joist. Just found this interesting.