Construction Purlin Flat Roof

They give added support to the roof and also provide a nailing surface for the end panels and drip edge.

Construction purlin flat roof.

The higher the snow load the closer the purlin spacing required. Metal roof purlins are installed horizontally under metal roofs. They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. Also known as sheeting rails purlins create the roofing members of the secondary framing of a steel building.

Purlins are an important component in a pre engineered steel structural kit. Or less x 1 1 cfu the flat use factor for applying the load to the wide face of a member. Purlin plates in wooden construction. Metal building roof purlins provide three structural functions.

Roof live load roof dead load x spacing x span of purlin 2. Purlin plates are beams which support the mid span of rafters and are supported by posts. Purlins are 2 by 4 feet and are installed much like metal roofing. A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin.

The common 4 on center design is suitable for snow loads up to 60 for most applications. The purpose of purlins. These structural supports run perpendicular across the rafter beams. The term plate means a major horizontal supporting timber.