Roof Purlin Types

Purlin plate principal purlin and common purlin.

Roof purlin types.

One of my questions was about snow loads. Secondary framing is an important component of many pre engineered metal buildings. In traditional timber framing there are three basic types of purlin. 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.

It is suitable to use for roof sheeting from fiber cement. I explained the layout of roof trusses and purlins on your building design. The type and spacing of purlins is a design consideration which depends upon the incident roof loads as well as the limiting lengths of sheeting to be used. For example decks and covered patios often use this type of purlin.

The table shows one 2 x 8 that will make a 15ft. As the bar is hollow caps are welded to the ends of the purlin to keep moisture from getting inside and corroding the metal. 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. They both can be combined well to make sure that the space below the roof.

Rectangular hollow section rhs is a type of purlin often used in roofs where the support structure will be visible when construction is complete. All about purlin span for metal roof. He gave me a copy of r802 5 1 3 rafter spans for common lumber species.