Blocking Between Roof Rafters

The most direct load path is for the roof sheathing to be edge nailed to blocking between each rafter.

Blocking between roof rafters.

Preventing rotation is typically accomplished by installing full depth blocking along wall plates between rafters and ceiling joists. Each block is 2x4 or 2x6 depending on the size of the rafters and is secured to the top plate. Rafter blocking is an essential part of the roof framing process in that the blocks provide a stop for ceiling insulation and a continuous surface for the roof sheathing to be edge nailed to. This load path is shown in figure 6 4.

Blocking or boundary member. Rotation loads on rafters occur when the roof sheathing is resisting lateral loads perpendicular to the rafter because these loads are actually trying to move the top edge of the rafter sideways. And often in a humid environment. Where the distance from the top of the braced wall panel to the top of rafters or roof trusses exceeds 151 4 inches 387 mm the top plates.

These connections could allow a greater uplift force to be resisted. The blocking panels will provide additional connections between the roof trusses and the top plate of the wall. That blocking is then nailed to the wall top plate with three 8d nails per rafter space as prescribed in irc table 602 3 1. Inches 387 mm or less blocking between rafters or roof trusses shall be provided above the braced wall panel in accordance with figure r602 10 8 2 1.