Steel Rafter And Purlin Roof Construction

Long spans and light weight make architectural such as cathedral ceilings exposed trusses and roomy lofts more feasible than ever.

Steel rafter and purlin roof construction. Note that these are normally only required to trussed rafter roofs and not for traditional purlin and rafter roof construction. They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. The support system for the roof is comprised of ridgepole and rafters or purlins. An affordable option and easier to lay than shingles tin is the most commonly used type of metal roofing.

For many applications a layer of plywood underneath your metal roofing is an unnecessary expense. 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. For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet. Let s take a look at the most common types of metal roofs for houses.

Purlins are 2 by 4 feet and are installed much like metal roofing. The purpose of purlins. Purlins and girts are used longitudinally to support the roof sheeting which they were originally designed for. They give added support to the roof and also provide a nailing surface for the end panels and drip edge.

J l neal subject. Building control guidance note purlin and rafter roofs timber sizes and construction details. Boxspan is extremely efficient in roof framing. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to.

Purlins are installed horizontally under metal roofs. The rafter and wall plate. We do recommend it however. This design is a lot stronger and more robust way of making a steel shed.

Do all roofing projects require purlins. In architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof. Roof frames rafters roof beams lintels. Also known as sheeting rails purlins create the roofing members of the secondary framing of a steel building.

Purlins are an important component in a pre engineered steel structural kit. The typical spacing standards for residential and commercial buildings are about 1 to 2 foot. 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.

These structural supports run perpendicular across the rafter beams. 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.