How Far To Span A Patio Roof Supports

Multiply the load per square foot by the total area of the roof.

How far to span a patio roof supports.

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. 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. If you move up to 4 by 8 you re usually allowed to span up to 10 feet between posts.

If an example roof is 10 feet by 20. The lengths and sizes of joists vary depending on the species and quality of the lumber used. 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. 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 smallest beams for patio covers are typically 4 by 6. 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. 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. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.

In general the maximum span for a 4 by 6 beam is 6 feet between 4 by 4 posts. The dead load is. 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. 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.