Wide Flange Beam Load Roof Rafters Span

The tables permit a bearing length of up to 3 5 inches but since 1 5 is probably the worst case that you ll encounter for joist or rafter bearing it s a safe value.

Wide flange beam load roof rafters span. Dead load weight of structure and fixed loads 15 lbs ft2. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. 1 ft 0 3048 m. You can make ads in the engineering toolbox more useful to you.

Live load 20 lbs ft2 956 n m2 maximum span ft in nominal size. W flange beams and allowable uniform load. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. The maximum spans in the table above are for the horizontal distance the rafter can span not the diagonal distance or actual length of the rafter.

Roof span table 16 17 roof span notes and cut length calculation 17 roof framing 18 roof details 19 20 roof load tables 21 framing connectors 22 23 table of contents welcome to ilevel ilevel is an exciting new brand and business within weyerhaeuser. Let s use this example and find a size of rafter that will work. According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2. For full table rotate the screen.

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. 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. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. 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.

Beams of more than one ply must be fastened together with either nails or bolts. Table 9 1 in span tables for joists and rafters figure 5 gives a required compression value of 237 psi for a span of 16 feet and bearing length of 1 5 inches. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Designation width x lbs ft nominal size depth x width inches x inches allowable uniform load lb span ft 8.

1 in 25 4 mm. 1 psf lbf ft2 47 88 n m2. So if your house is 26 feet wide and the roof ridge beam is centered on the house you will need a rafter that can span 13 feet. Anything 5 and above we always at least double cripple.