In a standing seam roof, long, single panels run vertically all the way from the eave to the ridge. In contrast, steel shingles are small panels installed in horizontal rows much like other shingles.

Small icicles are normal in the winter, roofing experts say, but larger icicles aren't. "Outdoors, the sheer weight of an ice dam can tear off your gutters or loosen your shingles. This ...