Pitched Roof Rafter Span Table

Here we have a wood framed gable roof.

Pitched roof rafter span table.

Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. Anything beyond that you are looking at using 2x6s for most sheds. Let s consider a basic gable wood roof framing design. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

3265 45 3220mm total span less ridge thickness 3220 2 1610mm horizontal span each rafter will cover and before meeting the ridge now when we turn to the 30 page in the rafter ready reckoner and when looking up the common rafter lengths one of the things it tells us is. Continuing on from part 3. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. The pitch and span of your roof will dictate how long of a rafter you ll need use maximum span calculator to help you find your rafter size.

Floor beam span tables of residential structural design we will now look at roof rafter and beam design. This will give us the span for each individual roof rafter. For pitched roofs flat roofs and ceiling joists. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

The figures are based on quality materials. Surveyors span tables for designing roof rafters. 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. In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.