Provision for Expansion — Tray Roofing

Non-ferrous tray roofing expands at about twice the rate of ferrous metals. Supported angle seam and double seam profiles must be installed using a balance of sliding clips to allow for expansion, and fixed clips to withstand gravity loads.

The position of the fixed clips depends on the roof pitch. The width of the fixed clip portion should be sufficient to install five clips at the required spacing.

Clips Positioning for Non-Ferrous Profiles as Determined by Roof Pitch.

Clip_positioning_by_pitch

 

Steel based angle seam and double seam profiles up to four metres in length can be laid without sliding clips. Roll cap and self-support tray roofing have clip systems that can accommodate thermal movement, and also do not require special sliding clips.

Using Clipped Flashings Minimises the Need for Rivets

Using clipped flashings to minimise the use of rivets is a feature of a well-installed standing seam roof.