Roof Truss Design Basics

On some roof trusses the 2 top chords extend down over.

Roof truss design basics.

Also in pairs with their high ends abutting on extremely long spans with a support underneath the high end. If roof slopes are not provided i e if the roofs are flat then it may be very difficult to provide sheet roofing without the use of effective mastic sealing of the sheet joints. Slope for roof is necessary to drain off rain water falling on the roof. Bowstring pitched and flat.

Incorporate overhanging top chords to add extra visual flair. The truss is a framework consisting of rafters posts and struts which supports your roof. It s often used for sheds garages or extension of an existing roof. Start by noting the exact length of the.

Common truss configurations for the most widely designed roof shapes. Size the bottom chord 0 25 inches 0 64 cm longer than the floor. The very first step for building roof trusses is to prepare a design layout that can be sketched by a professional architect or can also be done by using a software that is specifically meant to design a roof truss. A mono truss is a one sloped truss that forms a right angle triangle.

The basic design procedure is described in this section in terms of engineering design methodology architectural design examples and design variations. The second step in building a roof truss is to prepare the materials needed. Cut plywood gusset plates to fasten. As we will see below there are several different types of designs and this will impact the angles and designs of the overall truss.

Mono used where the roof is required to slope only in one direction. The information herein is written as an informative guide to residential wood roof truss construction and to provide an understanding of the basic design criteria of wood trusses. A mono truss roof allows for more sunlight and visual space proper drainage and relatively cheaper. Scissors provides a cathedral or vaulted ceiling.

Architectural style types of roofing material methods of support of column framing and relative economy are the principal factors influencing a choice among the three basic types of trusses. In addition side and end wall height and type roof shape and bracing requirements must be considered. Residential roof trusses as shown in figure a are an engineered configuration of wood members placed to hold the weight of the roof s finishing materials the internal structure s ceiling and any snow load that may occur. Designing your truss 1.