Roof Load Beam Span

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

Roof load beam span.

The theoretical size of a load bearing beam required to support a particular weight is easy to calculate but the choice of the actual beam depends on taking into account the factors of the particular situation. For the initial calculation f can be estimated at 1 000. The total load is 4 000 pounds. Standard 2 by 12 beams on 16 inch centers are used to span 15 feet.

Window door garage door headers supporting roof wall floor loads. It is important to list live load dead load and total load separately because live load is used to compute stiffness and total load is used to calculate strength. 50 psf x 14ft 700 pounds per lineal foot. An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry.

In the example the beam spans the 10 foot width of the roof. L stands for the span of the beam in feet. Tables providing size selections for various beam spans and loading combinations for southern pine dimension lumber and southern pine glued laminated timber are available for the following applications. 910 pounds per lineal foot.

Fill in the parts of the formula that are already known. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Window door garage door headers supporting roof loads only.