Profiled metal roofing – swarf staining

Cause

Swarf (residual fragments of steel from cutting, drilling or grinding roofing sheets) have been left on the roofing or in gutters

Repair

  • if staining is not severe, use a soft brush or cloth to wash the stained area with water and mild detergent; if necessary, use a nylon pot cleaner
  • if severe, scrub with a stiff bristled brush – do not use a wire brush. Prime the areas where the metallic coating shows through with an appropriate primer, then paint with at least two coats of acrylic paint