An affordable option and easier to lay than shingles tin is the most commonly used type of metal roofing.
Steel rafter and purlin roof construction.
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.
Purlin plates in wooden construction.
They give added support to the roof and also provide a nailing surface for the end panels and drip edge.
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.
Purlins should be fastened through the decking and into the rafters.
They give added support to the roof and also provide a nailing surface for the end panels and drip edge.
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.
For more detailed information on re roofing applications consult fabral tech nical bulletin 721 re roofing with metal.
The plywood covers the entire roof and is solidly attached to the rafters providing a sturdy base for both insulation and metal roofing panels.
A purlin plate in wood construction is also called an arcade plate in european english under purlin and principal purlin.
The purpose of purlins.
Metal roof purlins are installed horizontally under metal roofs.
Also known as sheeting rails purlins create the roofing members of the secondary framing of a steel building.
Let s take a look at the most common types of metal roofs for houses.
Metal building roof purlins provide three structural functions.
By supporting the rafters they allow longer spans than the rafters alone.
First the purlins support the roof.
Secondly purlins tie the rafters together stabilizing and strengthening the structure s rigid framing.
The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to.
They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top.
Do all roofing projects require purlins.
They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top.
The wider the roofing panels the greater spacing distance you should put.
Purlins are 2 by 4 feet and are installed much like metal roofing.
Contact fabral for additional information.
Load tables are available for all fabral panels.
This will provide a solid framework for attaching the metal panels.
Purlin plates are beams which support the mid span of rafters and are supported by posts.
We do recommend it however.
The metal roof purlins spacing must be done correctly within narrow tolerances.
While decking is not required for a metal roof and is often not used for shops barns or other outbuildings if a metal roof is being put onto a home or a garage the use of decking is common.
Whether you are looking to install a metal roof on a shed or a house it s important to know the difference in the various types of metal roofs available.
Purlins are 2 by 4 feet and are installed much like metal roofing.
The width of metal panels will determine the rafter spacing.
