Roof Truss Rafter And Purlin

Just as there are many types of roofs with many roof parts there are many different types of roof trusses this extensive article explains through a series of custom truss diagrams the different truss configurations you can use for various roofs.

Roof truss rafter and purlin.

Purlin plates in wooden construction. It is important to do inspection before you continue with the installation project. A notch in the rafter can be used on sloping purlins but a birds mouth is easier to locate and a quicker joint to cut on site. The rafter and purlin spacing for metal roof must be fitted to support the whole framework.

1 the purlin is easier built in or set in hangers at the gable walls. Purlin plates are beams which support the mid span of rafters and are supported by posts. As a verb rafter is to make timber etc into rafters. A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin.

The boards creating the slope of the roof are wider than lumber used to build trusses 2x8s 2x10s and 2x12s are most common in rafters vs. There are three types of purlins in wood construction. Parts of a traditional queen post roof truss. A common arrangement is a rafter and purlin system which combines purlins and rafters.

The roof support system is a ridgepole and either rafters which run perpendicular from the top of the walls to the ridge or purlins which run parallel to the ridge. Purlin plates under purlin principal purlins and common purlins. Roof purlin are members used to directly support roof sheeting materials and could be made of timber or steel. As nouns the difference between rafter and purlin is that rafter is one of a series of sloped beams that extend from the ridge or hip to the downslope perimeter or eave designed to support the roof deck and its associated loads or rafter can be a raftsman while purlin is a longitudinal structural member two or more rafters of a roof.

Rafter boards are fastened to the ridge board at the peak and the top plate where they join the wall. The term plate means a major horizontal supporting timber. In timber construction purlins are nailed to the rafter or supporting trusses while in steel roof construction they are welded or bolted to the rafters or trusses by the means of cleats. In finished space insulation is placed between the rafter boards and drywall or other material is fastened to the face.

While this article focuses on configurations we also have a very cool set of illustrations showcasing the different parts anatomy of roof trusses. 2 the purlins allow the rafter to be birds mouthed over them thus avoiding the tendency for the rafter to slide off the roof. To check if the framework is properly leveled and aligned if there are adjustments that needs to be created and so on.