Steel Rafter And Purlin Roof Construction

For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet.

Steel rafter and purlin roof construction.

Metal roofing panels rated for architectural use attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturer s instructions and local building codes. Whether you are looking to install a metal roof on a shed or a house it s important to know the difference in the various types of metal roofs available. They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. Purlins are installed horizontally under metal roofs.

In architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof. 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. Purlins are an important component in a pre engineered steel structural kit. Purlins and girts are used longitudinally to support the roof sheeting which they were originally designed for.

Long spans and light weight make architectural such as cathedral ceilings exposed trusses and roomy lofts more feasible than ever. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. Boxspan roof frames and rafters are suitable for use with both steel and timber framed homes. They give added support to the roof and also provide a nailing surface for the end panels and drip edge.

The purpose of purlins. Purlins are non pressure treated 1 x 4 x 12 lumber that is installed on to the roof in a specific layout pattern and screw pattern. Boxspan is extremely efficient in roof framing. Building control guidance note purlin and rafter roofs timber sizes and construction details.

The rafter and wall plate. Purlins are 2 by 4 feet and are installed much like metal roofing. In a structural steel shed the main portal frames and roof rafters are made from strong steel sections which are welded together and later bolted together. These structural supports run perpendicular across the rafter beams.

Do all roofing projects require purlins. Also known as sheeting rails purlins create the roofing members of the secondary framing of a steel building. This design is a lot stronger and more robust way of making a steel shed. An affordable option and easier to lay than shingles tin is the most commonly used type of metal roofing.

The support system for the roof is comprised of ridgepole and rafters or purlins. Let s take a look at the most common types of metal roofs for houses. Note that these are normally only required to trussed rafter roofs and not for traditional purlin and rafter roof construction. J l neal subject.

The typical spacing standards for residential and commercial buildings are about 1 to 2 foot. Roof frames rafters roof beams lintels.