For simple construction such as domestic construction this can be determined from span table supplements in as1684 2 and as1684 3.
Timber roof batten span tables.
Technical diagram on page 35 30mm m aximum allow able sp ans mm sheet roof spacing mm rafter size 600 760 900 1000 1200 66 x 30 850 750 700 700 600 90 x 30 1200 1050.
Joists crippled over supports shall be considered as single span joists.
Spacing should be interpreted as the centre to centre distance between adjacent parallel members.
Member tables for seasoned timber stress grade f17.
Stress grades and timber sizes combine to determine the spanning ability of load carrying members.
Lintel span sheet roofing tiled roofing roof load width rlw mm 1500 2100 4500 7500 1500 2100 4500 7500 maximum span of lintel mm 90 x 35 600 2000 1800 1400 1200.
Required size for a given span.
The high performance values of steel roof battens means they are an increasingly popular choice for reroofing or for new builds using tile roofs.
Table assumes a maximum flooring mass of 40kg.
Construction details should be in accordance with as1684 2.
Roof load width rlw and floor load width flw can be determined from as1684 or from the images below.
Timber queensland limited technical data sheet 19 pergolas and carports revised march 2014 page 3 pergola or carport beams tables 2l and 2h list the sizes and spans for pergola or carport beams in low wind speed and higher wind speed areas.
Span tables f7 rafters a maximum roof pitch of 25 degrees is assumed.
Timber battens for tile roofs must meet the requirements of as 1684 2 as 1684 3 or as 1720 1.