Timber Roof Purlin Span Tables

Alternatively you can use the lumberworx design tool.

Timber roof purlin span tables.

Purlin is a well known material in the field of architecture structural building or structural engineering. Span tables lumberworx has created the span tables below to assist in the specification of the lumberworx members. Surveyors span tables for designing roof rafters. For simple construction such as domestic construction this can be determined from span table supplements in as1684 2 and as1684 3.

All the figures are based on roofing tiles or slates laid on timber laths over sarking felt. Roofs and not for traditional purlin and rafter roof construction. It is a horizontal bar that used to support building at the roof structurally. Purlins near roof edges or changes of roof slope are subject to higher wind forces than interior purlins.

Pitched roof timber sizes. 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. Other more complex load condition spans can be determined with our free hyne timber design 7 5 software. The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.

There is an available purlin for every type of roofing material including purlin span for metal roof which is the most common material type to use this item. This free tool gives construction industry professionals the ability to design wall floor and roof members using the lumberworx product range. Building control guidance note purlin and rafter. If you have any questions about how to use.

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. For pitched roofs flat roofs and ceiling joists.