"This can be complicated. Is the common practice a butt joint with big screws or housings with clip angles and such. How do you all find the neccessary information to lay-out a hip or valley (especially with purlins with housings)? AutoCad, paper, pencil, triangles, etc?"
This isn't really complicated but it's harder to describe than it is to actually do. All the final dimensioning is done on-site with a calculator (usually trigonometry), with a printout of the angles and models of the joints for reference.
The first step is to find the dimensions between the working points at the intersections of the unadjusted rafter lengths. On a log Valley the ends are squared off. Then the compound angles at the peak and foot, and the backing trough, are cut.
The distances between purlins are laid out along the Valley trough line and the adjusted centerlines of the purlins are marked on the planes of trough. The traces of the pockets for the housings are projected to the irregular round on the Valley with jigs.
I have never seen an intersection simply butted and lagged. All roof members are housed, tenoned or step cut and the joints joints are supplemented with through bolts, knife plates or plates lagged from the surface of the roof.
Last edited by Joe Bartok; 01/02/08 03:46 PM.
