Chapter 1: Why do the hips and ridge on our 1920s house near Hiltingbury keep cracking?
What we find
A house from the 1920s was commonly roofed with machine-made clay or early concrete tiles, hung on small timber battens (the thin laths the tiles hook over) and nailed in places. The hips, where two slopes meet at an outward corner, were finished with capping tiles bedded in mortar. A hundred years of frost has loosened that bond, and the mortar shrinks away from the tile edges and drops out in pieces.
You may notice a crack running along a hip line from the pavement, or rubble in the gutter after a windy night. Inside, the signs are a damp patch on a bedroom wall just below the roof line, or a stain on the ceiling beside the chimney breast. The tiles themselves are often fine, which is why a repair so often beats a re-roof on these houses.
What we fix
We start by lifting a few capping tiles to see whether the bedding has failed or the timber beneath it has. If only the mortar is tired, we take the cappings off, clean them and refix them with a mechanical system, because BS 5534 now expects ridge, hip and verge tiles to be fixed in a way that does not rely on mortar alone. Dry-fix kits, covered by BS 8612, clip or screw the tiles to a batten over a breathable strip.
Dry ridge work on a semi-detached house is typically reported between £900 and £1,600, plus £300 to £900 for scaffold. Your fixed quote follows the survey. Any slipped tiles and corroded nails found along the way are replaced in the same visit. The choices are set out on our ridge tile repairs page.