This detail illustrates the connection of roof purlins to an interior rigid frame rafter where purlins from both sides lap over the rafter. This connection includes flange braces for lateral stability of the rafter.
The roof purlins bypass (lap over) each other at the interior rigid frame rafter, creating a continuous purlin line. The connection uses (6) 1/2" x 1-1/4" A307 bolts with (12) washers—one washer on each side of each bolt.
At the top of each purlin, a single 1/2" x 1" A307 fin head bolt with (1) washer secures the purlin flange to prevent rotation.
Rafter flange braces connect to welded flange brace clips on the rafter using (2) 1/2" x 1-1/4" A325 bolts with (4) washers. Refer to rigid frame drawings to determine if flange braces are required on both sides.
