Two homes in three in Prospect Park are two-family houses. In Haledon it is close to four in ten, and in Paterson about one in three. One roof covers both apartments, so when it leaks, the water can travel through the top unit and come out of a ceiling in the one below.
That is why we start at the roof and the attic, not at the stain. If the tenant agrees, we go through both apartments, so the fix lands where the water enters and not where it happened to drip.
A lot of these roofs have been patched more than once. We often find tar smeared around a chimney or a vent. Tar holds for a season or two. When we find it, we tell you whether the metal under it can be saved or has to be replaced.
From the sidewalk, any leak is a guess. We follow the water back to its entry point, and the photos reach you before any repair starts.