Vertical top hat sections supplied and fixed to the side rails by sheeting contractor.
Note: it is recommended that top hats are positioned close to the vertical side rail supports to avoid undue twisting of the rails with some of the heavier cladding systems.
Fixing and erection of the side rails, side rail supports and diagonal tie wires should be in accordance with the recommendations shown on Vertical Cladding Restraint Requirements, Vertical Cladding Restraint Fixing Details and Horizontal Cladding Arrangements.
Rail alignment to be provided by the steelwork contractor. Cladding support to be provided by the sheeting contractor.
Download our purlin technical manual for more information.