How Far To Span A Patio Roof Supports

The lengths and sizes of joists vary depending on the species and quality of the lumber used.

How far to span a patio roof supports.

Determine the load per square foot that the roof must support. For example you can span a 1 grade no knots southern yellow pine a greater distance than a 2 grade with knots southern yellow pine. Build your patio cover or deck designing with roof rafter span tables structural integrity of fir 6x6 beamspatio roof maximum beam rafter spans homepatio roof beam calculatorsingle ply beam solution professional deck. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.

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. Beams can be solid lumber or be built from lengths of 2 by lumber nailed together with 1 2 inch pressure treated plywood spacers in between this forms a 3 1 2 inch thick beam that is equal to the width of a 4 by post. The dead load is. Rafter and joist span faq.

How to size a beam to hold a porch roof. 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 an example roof is 10 feet by 20. 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 smallest beams for patio covers are typically 4 by 6. Multiply the load per square foot by the total area of the roof. The roof load is composed of a dead load and a live load. A 4 by 10 can usually span up to 12 feet between posts.