Purlin Metal Roof Structure

Metal building roof purlins provide three structural functions.

Purlin metal roof structure.

First the purlins support the roof. Purlin is a well known material in the field of architecture structural building or structural engineering. Purlins are 2 by 4 feet and are installed much like metal roofing. 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.

What is structural steel. Purlin plate principal purlin and common purlin. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. Purlins are also known as cold form or rolled form steel.

Secondly purlins tie the rafters together stabilizing and strengthening the structure s rigid framing. In architecture structural engineering or building a purlin is any longitudinal horizontal structural member in a roof except a type of framing with what is called a crown plate. A purlin shed is a structure where the main portal frames are made out of rolled formed sections usually c purlins. Welded together they can be used as columns braces and ties.

They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. 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. Engineered purlin metal mart offers a complete line of engineered purlin material. 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.

In traditional timber framing there are three basic types of purlin. They give added support to the roof and also provide a nailing surface for the end panels and drip edge. We do recommend it however. These purlins are made out of steel sheets that range between 1mm 2mm or 3mm steel.

Purlins are installed horizontally under metal roofs. 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 non pressure treated 1 x 4 x 12 lumber that is installed on to the roof in a specific layout pattern and screw pattern. Thirdly purlins add additional support between the spans of the individual framing bays.

It is a horizontal bar that used to support building at the roof structurally. The shape of cee purlins does not allow end lapping they are butted together. Metal building purlin spacing metal roofs are often referred as tin roofs in the past because of the use of tin such as aluminum or stainless steel sheets as the materials.