2x8 Roof Rafter Span

The loads are based on adjusted roof snow loads from the governing building code.

2x8 roof rafter span.

Roof loads rafter spans are tabulated for the most common roof loads. Live load is weight of furniture wind snow and more. Dead load weight of structure and fixed loads 15 lbs ft 2. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.

The pitch of the roof would be about a 4 pitch. There would be interior framing inside the addition but there would be an area of about 15 x 16 that would be clear. 1 ft 0 3048 m. Let s consider a basic gable wood roof framing design.

Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. Span calculator for wood joists and rafters also available for the android os. It is always better to have a large rafter rather than be concerned with a sagging roof. 1 psf lb f ft 2 47 88 n m 2.

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. Thanks for the responses yes the ridge will be centered on the 16 span. Wind classification n1 n2. 2 for design parameters refer to figure 7 26.

Continuing on from part 3. For roof live loads less than 20 pounds per square foot psf rafter spans and required e values tabulated for 20 psf shall be permitted to be adjusted in accordance with the follow ing table. Also available for the android os. Floor beam span tables of residential structural design we will now look at roof rafter and beam design.

If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof. Here we have a wood framed gable roof. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.

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. 3 where rafters are equal to or exceed four times their breath blocking should be used to reduce distortion. 1 refer to general notes for information that is relevant for all span tables. Pergola rafter spans for 600 mm and 900 mm spacing.

2 are indicated below. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.