Roof truss parts explained.
Ridge in roof truss.
Trusses are set onto the walls of a house and are tied together with horizontal boards called purlins.
The ridge board runs the length of the building and provides support for the tops of the rafters helping the whole roof structure work together as a system.
Since each truss is a complete frame trusses do not use a common ridge board and the purlins along with the roof decking provide lateral support.
The ridge board must be set as perfectly as possible so take your time and use careful measurements.
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.
Horizontal beams supported by posts and used to support the mid span of rafters to cover longer spans these are used in large buildings like the traditional large old barns in the us.
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.
Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3.
Height of rafter or top chord of truss.
Once the decking and roofing are installed a truss roof looks just like a stick framed roof.
Fabricating roof and floor trusses for the southeastern united states and the caribbean since 1959.
Rafter boards are fastened to the ridge board at the peak and the top plate where they join the wall.
Rafters have a tendency to flatten under gravity thrusting outwards on the walls.
Height of roofing materials including plywood shingles and ridge vent on metal roof add height of purlin insulation if any metal roofing and ridge vent building with trusses and metal roof.
Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge.
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.
The same thing is true for the bridge of the truss.
The more complex the truss framework is the greater quantity of these joints will be required.
One of a series of diagonal members of the truss that meet at the apex in order to support the roof deck and its loads.
A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to.
