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.
Roof purlin support.
The support system for the roof is comprised of ridgepole and rafters or purlins.
Once your purlins have been fitted and a supporting framework has been created you should look to carry out an inspection before you continue work.
With rafters it runs in perpendicular from the walls to the ridge while with purlins it runs to the ridge in parallel.
How to support roof purlins.
In architecture or structural engineering or building a purlin or purline is a horizontal structural member in a roof.
In architecture structural engineering or building a purlin or historically purline purloyne purling perling is a horizontal beam or bar used for structural support in buildings most commonly in a roof.
Using a combination of rafters and purlins is common.
Purlins can be fixed to rafters and all joins and laps should be supported by a rafter.