Using I Joists For Roof Rafters

Usp994 131 usp connector guide for trus joist.

Using i joists for roof rafters.

The manufacturer would need to design the repair. Yes you can use them for rafters they have to be installed per the manufacturers guidelines. Photo 2 shows a view of the other ends of these same i joist rafters and the use of. A framer s guide to the installation process.

Making top cuts in the i joists to make the short rafters one person held the tji down to the horses while another one made the cut. As a structural engineer i have inspected many roofs framed with i joist rafters but very few that have not needed a correction due to the i joist bearing. All nails shown in the details above are assumed to be common nails unless otherwise noted. While typically not a problem when the roof is flat and the i joists bear perpendicularly on the top plate when the rafters are sloped proper bearing becomes an issue.

Attach i joist to top plate using 8d nails at 6 o c. Tj 9510 installation guide for floor and roof framing with tji s31 s33 and s47 joists east canada. Use single i joist for loads up to 2000 plf double i joists for loads up to 4000 plf filler block not required. Tj 9001 installation guide for floor and roof framing with tji 110 210 230 360 and 560 joists.

I joists make for a strong flat roof but you have to pay attention to the connections at the ridge and eaves. 10d box nails may be substituted for 8d common shown in details. These i joist rafters are on 24 inch 61 cm centers and support plywood roof sheathing and wood shingles. The first thing to understand is how a roof framed with wood i joists differs structurally from a tradi tional stick framed roof.

When wood i joists are used as rafters connections at the structural ridge and the tops of exterior walls must be detailed properly. First they made i joist cross cutting jigs from osb scraps and made a few practice cuts. The one that is cut might be a problem. By the end of the class about 90 minutes they had two thirds of the tji roof rafters cut and ready for installation.