Purlin Shed Roof

Snap a chalk line horizontally across the roof two feet down from the top.

Purlin shed roof.

This design is a lot stronger and more robust way of making a steel shed. 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 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. Lay the first purlin at the ridge of the roof down to the chalk line beginning at either corner.

Fasten the purlin with 16d common nails into each vertical rafter. Metal building roof purlins provide three structural functions. Purlins and girts are used longitudinally to support the roof sheeting which they were originally designed for. Secondly purlins tie the rafters together stabilizing and strengthening the structure s rigid framing.

Insert two equally spaced nails into the rafter. 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. Thirdly purlins add additional support between the spans of the individual framing bays.