Installation: Curved Roofs

 Fitting curved sheeting requires considerable care to ensure a satisfactory and aesthetically pleasing job. Setting out requires first checking that the materials delivered on site are within specified tolerances, and before commencing work the building should be checked for squareness.

Both roll curving and crimp curving will produce a curve with the effective cover dictated by the forming process.  It is critical that the material is run to the correct width before being presented to the curving tool, or the effective cover of the straight portion will not match that of the curve. A variation of only 2mm between the straight and curved portion of a sheet will make it very difficult, or impossible, to install.

The curving process can cause dimensional changes, which can lead to misalignment, so the sheets should be kept square with the building. Some minor saw-toothing at the gutter end is to be expected when fitting curved sheeting. When multiple curves are required that cannot be provided on one sheet, the sheets should be fixed in the order shown below.

Fixing Order: Curved Sheets

Fixing-order_curved-sheets