Synopsis

In this segment, general contractor Tom Silva demonstrates to a homeowner the proper technique for removing moss and lichen from a shaded roof, offering advice on preventing their return. Joining him are plumbing and heating specialist Richard Trethewey, landscaping contractor Roger Cook, and host Kevin O'Connor, who pose the question: "What is it?" Upstairs in the loft, Richard illustrates how to fix a dripping valve by replacing the washer and valve seat. Subsequently, Roger assists a homeowne