How Do Attic Trusses Work

The trusses are tied to the walls with small metal plates.

How do attic trusses work.

The roof rises 4 inches in height for every 12 inches it runs horizontally. It s safer to use a crane for all involved. The trusses are fist stacked on top of the walls either by hand or with a crane. All trusses in a roof structure are designed for the worst possible combination of dead live and wind loads.

They are on 24 inch centers. These trusses went up in about four hours. While pitch and slope are used interchangeably they are not the same span also known as gable width this is based on the total footprint of the house and refers to the distance between two exterior. Trusses are typically set into place one at a time either by hand or with the help of a crane but in some cases some trusses can be assembled on the ground and lifted into place as a single sub assembly.

Attic conversions are now possible by replacing the truss rafters with a shaped trusses or horizontal beams which in return create additional space. A roof truss takes the weight of the roof and the snow on the roof if you live in that kind of climate and transfers it out into the load bearing walls of your house. Select build wall straight exterior wallfrom the menu then click and drag to draw a rectangular structure. Do you need a crane to set attic trusses.

The longer the truss and the steeper the roof pitch the larger the room. Trusses like all structures are devices for transferring loads from where you don t want them to where you do. While almost all trusses are made in a factory and trucked in site built trusses also are a possibility. Pitch this is the incline of the roof expressed as a fraction.

Because attic trusses require specific conditions to be met before they can be created we ll begin by drawing a simple structure that meets those requirements. The individual truss members are designed to restrain the corresponding forces i e tension or compression or a combination of bending with either the tension or compression force. A framing square will create the series of parallel lines and perpendicular lines if you simply slide it along one of the edges of the rafter. Once the trusses are up the roof is covered in plywood or osb which gives the roof tremendous rigidity.

Note that a framing square has two legs. Yes you ll need a crane because a typical attic truss weighs well over 100 pounds. An attic truss is a support feature found in many home or building attics. Select file new planfrom the menu to open a new blank plan.

The role of the horizontal beam is to tie the truss together and carry the load that would otherwise be sustained by the support and vertical timber also known as the king post.