Roof Truss Purlin Design

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.

Roof truss purlin design.

Structural design i steel structures prof. The same thing is true for the bridge of the truss. This article and series of illustrated diagrams shows you all the parts of a basic roof truss king truss and queen truss. Let s say you re planning to build a pole barn with only purlins and metal attached to the top of the truss while leaving the trusses exposed with no ceiling sheetrock.

Purlins supporting slate roof 120 n m 2. Sppu pune page 2 6b roof truss. In this case the truss loading is less so the cost of the trusses is less as well. Design cost framing more.

Plank or to still greater dimensions with heavier plank. Steel trusses offer increased strength faster installation and a longer life compared to wood frame pole barn trusses. By supporting the rafters they allow longer spans than the rafters alone. Generally the following figures may be adopted.

There are many types of roof trusses as wall as many types of roofs more types than there are parts. Industrial buildings are low rise structures characterized by their low height lack of. The complete guide to roof trusses. Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge.

The roof truss structure and design is integral to roof structural integrity and shape. Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. Purlin plates are beams which support the mid span of rafters and are supported by posts. The more complex the truss framework is the greater quantity of these joints will be required.

Pre welded purlin cups predrilled bolt holes and included mounting hardware for fast easy installation. These steel joints are needed to support the overall truss. The size of purlins depends on the nature of roof covering supported wind and other loads and the spacing of the trusses. Purlins supporting glazed roof 100 n m 2.

Sheathing to 7 to 9 ft with 2 in. As structural members they resist loads and provide lateral restraints for truss members therefore it is important to design them properly against forces. We provide angle iron steel trusses in gable lean to and header styles. A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin.

Purlins supporting corrugated sheeting 80 n m 2. Purlin plates in wooden construction. The term plate means a major horizontal supporting timber.