I Joist Used As Roof Rafters

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.

I joist used as roof rafters.

No solid sawn conventional lumber should be used as rim joist with i joist. Because i joists are straight and true it s easier for builders to avoid crowning and maintain a level framing surface. Again put them closer together if you want to achieve a greater span. These i joist rafters are on 24 inch 61 cm centers and support plywood roof sheathing and wood shingles.

Should not be cut like near the b vent. They are ideal for long spans including continuous spans over intermediate supports. Trus joist tji s31 s33 and s47 joists for use in eastern canada. There s no reason to used i joist with a 15 span.

Can span over 18 for gable roofed shed. I joists make for a strong flat roof but you have to pay attention to the connections at the ridge and eaves. Looks like they can be used as rafters. 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.

Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. Shall be permitted to be used. Insulation should be 1 inch from b vent. When wood i joists are used as rafters connections at the structural ridge and the tops of exterior walls must be detailed properly.

With an 8 soffit your rafter without a ridge deduction is roughly 20 4 3 4. Use 2 6 rafters if your roof will experience heavy snow or wind loads. Just found this interesting. 6 8 sloped bearing conditions.

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. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. All you need is 22 2x10 s or 2x12 s. An spf rafter can span nearly 15 at the same dimensions.

I joists are used extensively in residential floor and roof framing. It is always better to have a large rafter rather than be concerned with a sagging roof. Pdf says to consult with specific manufacturer for design installation specs.