A.Todd Miller, president of Classic Metal Roofing Systems, responds: Even though I don't know of any manufacturers who recommend this as part of their standard installation procedure, painting the cut edges of steel roofing wouldn't be a bad idea.

While most manufacturers offer matching touch-up paints, all you would actually need to do is rig up some simple method (brush or roller or dip tray) and apply a quality rust-inhibiting primer or paint.

It's also worth pointing out that metal panels should be cut with shears — rather than with an abrasive blade — to eliminate the possibility of creating hot metal shavings that could burn through paint coatings and cause rust.