Rafter and roof joist spacing is only one part of a complex roof design that works together to form a structure that meets building codes and can hold up the weight of the roof and roof load.
Roof rafter spacing australia.
They are also engineer certified to meet as 1684 2 2010 and wind loading requirements up to n4.
1 refer to general notes for information that is relevant for all span tables.
Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.
Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches.
But they do tend to space rafters in one of several industry standard increments typically.
Wind classification n1 n2.
Live load overhang kpa.
Builders aren t bound by standard rafter spacing measurements.
If your local building authority has a rafter spacing code you may not space rafters wider than required by code.
Pitching beams 23 common installation details 25 notches cuts and holes in beams.
Rafters 12 ceiling joists 15 hanging beams member16 underpurlins 17 strutting beams 18 roof beams 20 verandah beams 22 garage roof.
If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.
It is always better to have a large rafter rather than be concerned with a sagging roof.
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.
A maximum roof pitch of 25 degrees is assumed.
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.
Technical diagram span tables f7 rafters on page 35 30mm m aximum allow able sp ans mm sheet roof spacing mm rafter size 600 760 900 1000 1200 66 x 30 1250 1150 1050 1000 950 90 x 30 1650 1550 1550 1400 1300 138 x 30 2600 2300 2150 2000 1800 185 x 30 3000 2650 2450 2350 2150 230 x 30 3050.
We also supply e battens at 65mm x 35mm in 6 3 metre lengths to match truss and rafter spacing.
Rafters must be strong enough to hold the roof sheathing and the shingles.
3 where rafters are equal to or exceed four times their breath blocking should be used to reduce distortion.
Tables such as those for rafters.
This is an exciting product made from structural laminated veneer lumber lvl that meets the as nzs4357 standard.
Roof area supported post a post b rafter overhang half rafter span hot dipped galvanised stirrup top of footing slopped away from post concrete footing or rammed earth back ll 100 mm 75 mm course gravel laid at the base of the post concrete footing a fixed to stirrup b embedded in ground figure 3 installing posts beam overhang.
Loads are calculated in accordance with table 3 1 of as nzs 1170 1 2002.
