Roof Purlin Details

Bridging and purlin accessories are manufactured from steel with a minimum yield of 300 mpa and galvanised coating of z275 or zinc aluminium alloy az150 coating.

Roof purlin details.

Purlins traditionally support the roof deck cladding sheeting and are in turn supported by the principal rafters steel beams etc. 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. It is often used in simple roof trusses such as in the shed porch and garage. Purlin is a well known material in the field of architecture structural building or structural engineering.

Minimum number of spans is 2 and the maximum span is 12 5m. In the past the majority of roof structures were of wooden construction but over the past 15 to 20 years there has been a vast shift away from wood to metal mainly steel roof construction. Roof hugger retrofit sub purlins are zee shaped structural members that are typically 10 to 12 feet in length. Stramit purlins and girtsare manufactured from hi tensile g450 g500 or g550 galvanised steel with a minimum z350 galvanised coating 350g m2.

It is a horizontal bar that used to support building at the roof structurally. Details on page 45 load tables on page 33 sleeved double span system sleeves are provided at all penultimate supports and are staggered at internal bays. The support system for the roof is comprised of ridgepole and rafters or purlins. In traditional timber framing there are three basic types of purlin.

In architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof. In a nutshell it s made up of a central vertical post called the king post two rafters meeting at the apex and a tie beam or the horizontal base. And roof pitches within the limitations given in this manual. The king post roof truss is the simplest of the trusses because of its simple composition.

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. Purlin plate principal purlin and common purlin. A 2 nominal lumber thickness provides the maximum pullout values for both screws and nails when the fasteners penetrate a. There is an available purlin for every type of roofing material including purlin span for metal roof which is the most common material type to use this item.

Purlins girts and roof deck the substructure to which the metal panels are fastened must be properly spaced and sufficiently thick to provide a roof or wall system able to meet required design loads. Using a combination of rafters and purlins is common. The use of purlins as opposed to closely spaced rafters is common in pre engineered metal building systems and both the ancient post and beam and newer pole building timber frame construction methodologies.