How to Build Roof Trusses

A roof truss, also referred to as rafter, forms the skeleton of the roof. It carries the weight of the roof deck and the framing, and supports the walls. In houses with more than two floors, a truss is important. It also prevents the walls from bending or flexing. It carries the load of the roof, sheathing, roof beams and ceiling materials, which together is called the 'dead load'. While the load of snow, wind and all movable furnitures of the floor above, is referred to as 'live load'.

The roof trusses are usually connected together with tooth-like metal plates, made from galvanized metal. They are connected together in a triangular fashion. Roof trusses are made of materials like aluminum, steel, timber, etc. However, the most preferred material is wood, as for many people it is a symbol of reliability and friendliness. The material for building roof truss is mainly chosen by the roof architect and the owner, based on the budget.

Building Roof Trusses

Before building roof trusses, a layout for the same should be prepared. Below mentioned steps will guide you on how to build roof trusses.

Method 1:

• The things required for building roof trusses are timber, galvanized steel truss plates, saw, hammer, nails, and 1 ½ inch galvanized screw.
• Cut the timber according to the size of the roof, keeping in mind the local building standards.
• The thickness of the timber depends on the weight it has to support however, timber of size 2*6 and 2*8 is mostly preferred.
• Galvanized steel connector plates are used for holding the timber together. The timber is connected together in a triangular fashion, and are bolted together with screws that are at least 1 ½ inch long.
• Add a brace of size 2*4, that dissects the center of the triangular timber. For trusses having load bearing function, add a support at 90 degree angle from the bottom of the center.
• Attach trusses to the frame, leaving an appropriate overhang. The amount of overhang is usually decided by the architect, depending upon the size of the house and the pitch of the roof.
• Attach the trusses at a distance of two feet and secure them with three inch desk screws.
• For final support, sheath the roof trusses.

Method 2:

• A metal can also be used for the construction of a roof truss. It can be aluminum, tin or even steel.
• Cut the material according to the size of the roof truss. Use this roof truss as a pattern for cutting other pieces.
• Cut the steel gussets. This will indicate the number of nails required and also the spacing required for the front and back nailing pattern.
• The gussets are used for connecting a single side of the last roof truss.
• Nail down the truss connections on a solid surface in such a way that they penetrate all the gussets.
• Lay the framing members and check if they align properly with the truss.
• Stack all the roof trusses for installation.

As it is said, the base of the roofing should be strong enough to carry the weight of the apex. Similarly, firmer the roof truss, firmer will be the house. Following the steps on how to build roof trusses, you can make your roof truss strong enough to carry the heaviest weight.