Roof Truss Span Distance

For example a roof with a span of 20 ft and a rise of 7 feet needs rafters that are the square root of 400 49 21 2 feet.

Roof truss span distance.

Typical roof truss. Already having the rise will make it easy to determine the rafter length by loading the numbers into the equation chart. Standard roof truss spacing. For example in the rafter span table below the highlighted cell in the 40 live load table indicates that 2 x 8 southern yellow pine joists that have a grade of 2 that are spaced 24 apart can have a maximum span of 10 feet 3 inches 10 3 if designing for a live load of 40 lbs ft 2.

This means that if you re in charge of repairing or installing roofing trusses you ll be expected to hold to these standards. These standards are as follows. C rafter length. Bt b tc 6 6 common truss configurations for the most widely designed roof shapes.

Mono used where the roof is required to. To achieve maximum indicated spans trusses may require six or more panels. Overhang this is the extra part that extends beyond the exterior wall of the home. Equation a2 b2 c2.

Contact your localalpine trussmanufacturerorofficeformoreinformation. Trusses with an asterisk that exceed 14 in height may be shipped in two pieces. Span also known as gable width this is based on the total footprint of the house and refers to the distance between two exterior walls.