Residential Roof Truss Spans

Here s a common truss design.

Residential roof truss spans.

Click to add item 26 spreadweb residential roof truss 6 12 pitch 87 to the compare list. Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. Maximum deflection is limited by l 360 or l 480 under live load. Just as there are many types of roofs with many roof parts there are many different types of roof trusses this extensive article explains through a series of custom truss diagrams the different truss configurations you can use for various roofs.

Included are a series of representative roof truss span tables that will give you an idea of the truss spans available for a particular load condition load duration lumber type and truss configuration. The typical overhang for residential is between 16 inches and 24 inches. If the overhang extends beyond 24 inches say to 30 inches then a 2 6 top chord for the tail section will be required to handle the additional overhang. Post frame trusses are designed to be placed at spans greater than two feet on center.

While this article focuses on configurations we also have a very cool set of illustrations showcasing the different parts anatomy of roof trusses. Basic lumber design values are f 2000 psi f 1100 psi f 2000 psi e 1 800 000 psi duration of load 1 00. Custom trusses up to 100 span. When making a selection below to narrow your results down each selection made will reload the page to display the desired results.

Shop roof trusses spacer floor truss. 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. Spread web storage trusses are engineered to have a small area to allow storage within. Overhang this is the extra part that extends beyond the exterior wall of the home.

These allowable spans are based on nds 91. 8 10 foot 1 10 foot 1. Again this length can be adjusted to fit the need of the truss. The same is true if we make it steeper.

If we go any larger it will require more webbing inside the truss which will directly affect the cost of the truss. Post frame trusses can be used for agricultural residential commercial or industrial use. This 26 span truss with a 4 12 roof pitch is the most economical truss we can build. They have not been updated for the change in lumber values within the last decade.

Keep in mind that these tables are for estimations only.