Roof Framing Plan Roofing C Purlins

The roof support system is a ridgepole and either rafters which run perpendicular from the top of the walls to the ridge or purlins which run parallel to the ridge.

Roof framing plan roofing c purlins. They vary in size depending on length and spacing. In addition our c section purlins can also be used for door framing roof trimming window trimming parapet rails and side rails also see z purlins. Welded together they can be used as columns braces and ties. The steel purlins are in turn supported by rafters or walls.

Rafters rafters make up the main framework of all roofs. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. Roofing terms when framing a roof figure 7 2 carpenters must be familiar with commonly used roofing terms figures 7 3 and 7 4. They are inclined members spaced from 16 to 48 inches apart.

The purlins support the long span steel roofing but before the roof itself is put on a metal facia frame is installed around the perimeter of the roof. Secondary framing is an important component of many pre engineered metal buildings. C section purlins or cee section purlins are designed to form the walls and floor joists of a building shell structure making them also ideal for supporting beams needed for mezzanine flooring. This frame supports and is hidden by a metal facia board.

Also referred to as secondary structurals this type of framing runs in between primary framing elements creating a structure within a structure much like cross beams in a wooden building. The shape of cee purlins does not allow end lapping they are butted together. Purlins traditionally support the roof deck cladding sheeting and are in turn supported by the principal rafters steel beams etc. Our frame is welded up of 1 x 1 angle bar and 1 flat bar.

A common arrangement is a rafter and purlin system which combines purlins and rafters. 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. 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. In steel construction the term purlin typically refers to roof framing members that span parallel to the building eave and support the roof decking or sheeting.

Metal c purlins are light in weight and perfect for simple span construction.