Steel Roof Purlins Design

If your design or local building codes demand extreme spans or snow loads taller purlins may be required.

Steel roof purlins design. The typical roof structure now consists of steel i beam rafters placed approximately 10 feet this varies depending on purlin size and other variables apart with either 4 6 or 8 lightweight steel purlins installed horizontally across the rafters. Do all roofing projects require purlins. Available in cee or zee shape red oxide primed or galvanized 16 14 or 12 gauge sizes from 4 up to 12 flange widths of 1 1 2 up to 4 cut to your specified lengths hole punching available load tables available for all material. Purlins are 2 by 4 feet and are installed much like metal roofing.

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. Civil engineering design in architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof. Roof purlin are members used to directly support roof sheeting materials and could be made of timber or steel. Metal roof purlins are installed horizontally under metal roofs.

The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. They expand and contract reasonably in extreme temperature changes. Welded together they can be used as columns braces and ties. In timber construction purlins are nailed to the rafter or supporting trusses while in steel roof construction they are welded or bolted to the rafters or trusses by the means of cleats.

They are light weight dimensionally stable accurate and straight. Steeline c purlins are available in different sizes and material strengths to match the design specification of your building. They give added support to the roof and also provide a nailing surface for the end panels and drip edge. Engineered purlin metal mart offers a complete line of engineered purlin material.

They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. Taller purlins also allow room for increased insulation. Purpose use cee purlins are secondary steel framing members most commonly used as roof purlins wall girts and header jamb and sill for windows and doors on metal buildings. The shape of cee purlins does not allow end lapping they are butted together.

Steel purlin is a direct replacement for wood purlin. 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.