Traditional Rafter And Purlin Roof Construction

There are three types of purlins in wood construction.

Traditional rafter and purlin roof construction. Sizes used in traditional roofing construction. The overall construction of a traditional cut roof is to ensure that the load of the roof is evenly transmitted to the walls below. Building control guidance note purlin and rafter roofs timber sizes and construction details. They span from the wallplate to the ridge board providing a platform for the underlay battens and tiles.

The rafters are the main load bearing elements of the roof. Parts of a traditional queen post roof truss. Purlin plates under purlin principal purlins and common purlins. A common arrangement is a rafter and purlin system which combines purlins and rafters.

By supporting the rafters they allow longer spans than the rafters alone. Purlin plates are beams which support the mid span of rafters and are supported by posts. Traditional or cut roofs usually comprise a series of sloping timbers rafters fixed to a wall plate at their feet and a ridge board or possibly a wall plate at their head. A cut roof this is the traditional method of cutting the timber on site and building up the roof using rafters ridge boards joists and purlins etc the exact details being determined by the size of roof size of timbers etc.

The term plate means a major horizontal supporting timber. 10 complex new roofs. 7 simple traditional roofs. Note that these are normally only required to trussed rafter roofs and not for traditional purlin and rafter roof construction.

The longitudinal horizontal beam that is sitting on a post or the principal rafter of a truss and used to support common rafters. There are two basic methods of pitched roof construction. Purlin plates in wooden construction. 11 some examples of older traditional roofs.

Pitched roof construction. All the figures are based on roofing tiles or slates laid on. In architecture structural engineering or building a purlin or historically purline purloyne purling perling is any longitudinal horizontal structural member in a roof except a type of framing with what is called a crown plate. 9 complex purlin roofs.

Exposed rafters are a feature of some traditional roof styles. The roof support system is a ridgepole and either rafters which run perpendicular from the top of the walls to the ridge or purlins which run parallel to the ridge. A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin.