Timber Roof Purlin Span Tables

For simple construction such as domestic construction this can be determined from span table supplements in as1684 2 and as1684 3.

Timber roof purlin span tables.

Purlin is a well known material in the field of architecture structural building or structural engineering. 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. For pitched roofs flat roofs and ceiling joists. Building control guidance note purlin and rafter.

Other more complex load condition spans can be determined with our free hyne timber design 7 5 software. This free tool gives construction industry professionals the ability to design wall floor and roof members using the lumberworx product range. It is a horizontal bar that used to support building at the roof structurally. The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.

Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings. Surveyors span tables for designing roof rafters. All the figures are based on roofing tiles or slates laid on. The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.

Span tables allow users to choose an appropriate size and stress grade to achieve spanning needs. Roofs and not for traditional purlin and rafter roof construction. If you have any questions about how to use. Pitched roof timber sizes.

Purlins near roof edges or changes of roof slope are subject to higher wind forces than interior purlins. Span tables lumberworx has created the span tables below to assist in the specification of the lumberworx members.