Chapter one
Pantiles and render on Sea Lane
Moderne houses under pitched roofs, sometimes of pantiles, meet their white render at junctions that need watching.
The Goring appraisal describes the detached houses on Sea Lane as mainly 1930s, with those on the west side built by Hesketh Estates in the moderne style: white-painted render under pitched roofs, sometimes of pantiles. A pantile is an S-shaped tile that laps its neighbour sideways, so the roof is a single layer and every tile depends on its own fixing. A plain-tile roof is different, because two layers overlap and a loose tile still has a second one behind it. When a pantile slips, little stands between the weather and the underlay.
At a glance
- Sea Lane's detached houses date mainly from the 1930s
- Their roofs are pitched, sometimes with pantiles
- A pantile roof is one layer; each tile needs a fixing
1.1 Verges, abutments and render
Rendered walls and pitched roofs meet in two places. At the verge, the sloping edge above a gable wall, the last tiles are held down by mortar or by a dry-fix verge unit, and mortar there cracks and lets tiles loosen. At an abutment, where a slope runs into a wall, lead is tucked into the render or into a chased joint. Render can crack along the top edge of that lead and carry rain behind it, which shows up as damp on a wall inside the house rather than on a ceiling. We examine both places with the render in mind, because a coat of paint does not stop a crack that moves.
1.2 What a pantile repair involves
BS 5534 expects each single-lap tile to have a mechanical fixing, at least one according to Wienerberger, and Marley adds that tiles round the edge of a roof are fixed twice. Where nails have rusted away or were never driven home, we re-fix the tiles with nails or clips to that standard, and we replace any that have cracked. Pantiles come in several profiles, so we match the shape before ordering, not after. Where a house has only a few loose tiles, the job stays small. We also look from the loft side: a chink of light along the ridge, wet rafters and a perished underlay show how far the problem has travelled. Where the battens beneath have rotted, the photographs make that plain and the quote covers the wider work, as our pitched roofing page explains.
Re-fixing a pantile roof
- Lift one We raise a pantile and look at the nail, the batten and the underlay beneath it.
- Map the loose Slipped tiles are marked on a roof plan, with photographs of each slope.
- Match the profile Any replacement is chosen to fit the S-shape and size already on your roof.
- Fix and check Each tile is fixed mechanically, and the verge and abutment lines are rechecked.
