Albion Zed purlin systems:

Single span butt system

Used where purlin sleeves cannot be utilised e.g. purlin within rafter depth.

Double span butt system

Used where purlins may double span over the rafter but uses only one sleeve per run.

Sleeve system

The most popular system employs sleeved joints to provide full continuity over the support rafters.

Heavy end bay system

Used on larger buildings (5 bays or more) where heavy end bay / inner bay sleeves are utilised to reduce the gauge of inner bay purlins.