For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
Lumber span tables 2x4 flat roof rafters.
For heavy loads 2x4s can span up to 5.
Span tables for jois ts and rafters american wood council 4 span tables for joists and rafters american wood council design criteria.
Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
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.
Limited to span in inches divided by 360.
1 ft 0 3048 m.
Deflection for 30 psf live load.
2 4 rafters can span up to 7.
Ceiling joist span use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size.
Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.
Lumber design values use of these span tables requires reference to the applicable design values for the various species and grades of lumber.
Span calculator for wood joists and rafters also available for the android os.
Spacing your 2 4 shed rafters at 24 on center limits the width of your roof.
Dead load weight of structure and fixed loads 15 lbs ft 2.
Tables w 1 and w 2 of design values for joists and rafters a supplement to these span tables provide such values for the most commonly used.
2 are indicated below.
Live load is weight of furniture wind snow and more.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
Strength live load of 30 psf plus dead load of 10 psf determines the required bending design value.
Permitted for intermediate spans and design values.
Also available for the android os.
For light load roofs 24 o c.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
View joist rafter tables.
Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall.
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.