Chapter one
Plain clay tiles on Rustington's flint barns
A plain tile roof is built from hundreds of small tiles, and keeping one sound means matching each repair to what surrounds it.
The Arun conservation statement for Rustington singles out flint walls as a characteristic of the whole conservation area, and it names North Barn and Manor Barn, an early or mid-19th-century building, as flint under plain clay tiles. Plain tiles are the small, slightly curved clay tiles that overlap in many courses, each one hung from a timber batten, a narrow strip fixed across the rafters. Because each tile is small, a roof holds hundreds of them, each a spot where a crack or a slipped nib can let water in.
At a glance
- Plain tiles are small and laid in overlapping courses
- Pitch limits depend on the individual tile
- Old peg-tile roofs defy the usual lifespan figures

1.1 Pitch and the individual tile
A tile will only shed water properly above its minimum pitch, and the figure differs from tile to tile. Marley lists its Canterbury clay plain tile at 40 degrees, Ashdowne at 35 and Hawkins at 30. Natural slate, for comparison, is put at 20 degrees by BS 5534. Before we agree any re-covering, we measure the slope and check it against the data sheet of the tile proposed. A tile laid below its limit leaks however well it is fixed.

1.2 How long they last, and what a repair involves
Marley quotes a minimum life expectancy of 60 years for clay tiles. A Building Conservation Directory article says the 60-year figure is no safe yardstick for old peg-tile roofs, a fair warning for a barn roof that has stood since the 19th century. We judge by condition: how many tiles have cracked or lost their nibs, how sound the battens are, and whether the nails have rusted through. Sound tiles are lifted, sorted and reused, and gaps are filled with tiles matched for size, colour and camber. Our pitched roofing page covers re-covering in more depth.
1.3 Tiles on the walls as well
Ffynches Lodge has decorative vertical tiling, meaning tiles hung on the wall as a cladding. Where that cladding meets a roof slope, the water is carried by lead soakers, small folded sheets bent under each tile course, and by flashings above them. These details sit in shade and are rarely looked at, so they fail unnoticed. We trace damp in an upper-storey room back along the wall before we blame the roof, and the survey photographs in your quote show where the water was getting in.
Minimum pitch for some common coverings
| Covering | Minimum pitch |
|---|---|
| Marley Canterbury clay plain tile | 40 degrees |
| Marley Ashdowne clay plain tile | 35 degrees |
| Marley Hawkins clay plain tile | 30 degrees |
| Marley Lincoln clay pantile | 15 degrees |
| Natural slate (BS 5534, moderate exposure) | 20 degrees |




