Span Tables Roof Purlin Spacing Australia

Use recommended minimum roof pitches as specified by roof sheet supplier.

Span tables roof purlin spacing australia.

They have been generated using the latest version of the purlin and girt software developed by the centre for advanced structural engineering at the university of sydney and cover the full range of stratco z and c sections from 75mm through to 400mm depth. If the space between posts is greater than 8 feet then brace is needed to avoid buckling. Safe roof purlins spans. Spacing should be interpreted as the centre to centre distance between adjacent parallel members.

For 2x4s purlins the posts are spaced in 4 feet distance. Joists crippled over supports shall be considered as single span joists. All spans to have 1 row of bridging. Step 4 assume the wind classification for the area is n1 and the roofing profile is stramit corrugated cladding 0 48mm bmt thickness in a single span configuration.

Spantec has prepared these tables for use by people skilled in the design and specification of the. The tables include a comprehensive range of span configurations. Purlins near roof edges or changes of roof slope are subject to higher wind forces than interior purlins. Cleated or bracketed fixing only no flange bolting.

Rafter or uss spacing w lintel span sheet roofing tiled roofing roof load width rlw mm 1500 2100 4500 7500 1500 2100 4500 7500 maximum span of lintel mm. Roof load width rlw and floor load width flw can be determined from as1684 or from the images below. Cpe 0 9 and cpi 0 2. 29 norfolk close tuncurry nsw 2428 phone.

High pressure zones kl 1 5 and 2 0 included. As per as1684 and as4055 spanman adopts a nett pressure coefficient applied along the full length of the purlin of cpn 2 0 for non cyclonic zones n1 to n6 and cpn 2 5 for cyclonic zones c1 to c4. Reading off the empty under table with h 5m hc 2 5m span table c will be used to determine the spans. Table assumes a maximum flooring mass of 40kg m2.

The safe spans below are suitable for sheds and class 1 structures with the following assumptions. If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts. Flat roof span tables allow for a maximum roof pitch of 5º. Required size for a given span.

From span table c the maximum allowable single span is 2160mm. 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. 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. For 2x6s purlins the posts are spaced in 6 feet distance.