Purlin Roof Structure Names

The roof truss structure and design is integral to roof structural integrity and shape.

Purlin roof structure names.

Dead load will be the actual weight of the roof steel and the roof purlins. A horizontal timber or metal resting at the peak of the roof the rafters and trusses are connected to the ridge board for a cohesive framework. Purlin plates are beams which support the mid span of rafters and are supported by posts. Internal roof elements to consider during loft conversions consist of a number of sub structures such as ridge boards rafters purlins joists wall plates and steel beams.

Under purlins were typically propped off internal walls. This beam is known as purlin. Double roof construction is simple than other roof. A composite decking made of solid materials it resembles real wood and particularly strong and stable for bearing heavy load.

This support is usually a beam which is protected under the rafters at a point between the ridge and the wall plate. It is a waterproofing layer made of regular felt stacked above the solid. A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin. The term plate means a major horizontal supporting timber.

There are many types of roof trusses as wall as many types of roofs more types than there are parts. Below is a sketch of the original roof wall structural details for this building. The cos of the purlin spacing is because the load on the purlins is vertical and the purlin spacing is with the run of the roof. The two words are often used interchangeably and both are long strips usually wood used for the attachment of roofing material.

For example an 8 x 4 under purlin would support the center of a row of 6 x 2 rafters that in turn would support 3 x 2 roof purlins to which the roof. For sake of discussion we will assume a minimal roof snow load of 20 psf pounds per square foot and a 4 12 roof slope. The roof structure above can be seen near completion near the end of our roof dormer types article. In the roof space as the name suggests the ridge board is the length of timber which runs horizontally along the apex of the roof.

The original roof was built using purlins beams extending between gable ends. By supporting the rafters they allow longer spans than the rafters alone. In lightweight timber roof construction under purlins were used to support rafters over longer spans than the rafters alone could span. Purlin plates in wooden construction.