Types Of Joints

There are three main systems used for joining fully supported roof cladding which apply to all metals:

• The Standing Seam.
• The Double seam (see Standing Seam).
• The Angled Seam.
• The Roll Cap.

The roll cap is a variation of the standing seam because it has two standing seams one on either side of a square or trapezoidal timber batten. The double seam and angle seam has only one seam.

Conical roll and other types of jointing have been used in the past, but the most common systems are outlined below. The thermal movement across the width of metal panels is taken up by the provision of a gap at the base.