Hi, I don't know about any where else, but in my area, pole barn roofs have the purlins on top of the rafter or truss when metal roof is used. I can't find anywhere how to draw them this way in CA. Should be drawn as one continuous member, not broken up at each rafter or truss like blocking is drawn.As long as CA has been around this should have been a common design option. Please help if there is an easy way of doing this I don't know about. Thanks