Purlin Roof System

The butted purlin system is suitable for all building types but is primarily used in single span applications.

Purlin roof system. Download our purlins brochure. It is the simplest purlin system and can be used in inset and oversail configurations. Non standard end configurations can be accommodated as required. Purlins traditionally support the roof deck cladding sheeting and are in turn supported by the principal rafters steel beams etc.

Purlins support the loads from the roof deck or sheathing and are supported by the principal rafters and or the building walls steel beams etc. A common arrangement is a rafter and purlin system which combines purlins and rafters. In the past the majority of roof structures were of wooden construction but over the past 15 to 20 years there has been a vast shift away from wood to metal mainly steel roof construction. 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.

Purlin roof structure civil engineering design in architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof.