Chapter one
Brick stacks, gables and the Reeds Lane brickworks
Brick made locally in the 19th century survives as stacks and gable walls, and the roof joins beside them are where water gets in.
Mid Sussex District Council's appraisal of Hurstpierpoint records that, in the 19th century, one of the parish's three brickmaking sites was at Reeds Lane in Sayers Common. Brick is therefore part of how this village was built. It is also a material that tells you about a roof. A chimney stack is the tallest and most exposed piece of brickwork on a house, with rain driving at four faces and frost working into any joint that has opened. Over time the faces of the brick can flake away, which is called spalling, and the mortar between them wears back until the stack stops shedding water.
At a glance
- Reeds Lane was one of three parish brickworks
- Frost flakes the faces of exposed brick
- Stack leaks often start at the flashing

1.1 Stack, flaunching and lead
A stack leaks in three places. The flaunching is the sloping mortar bed on top that seats the pots, and a crack in it sends rainwater straight into the flues below. The flashings are the lead bands where the stack meets the slope; if they lift, water tracks inside the roof and shows up as a brown stain on the wall of the chimney breast. The brickwork itself is the third, because open joints let rain in sideways. We look at all three from the loft and the ladder, and the repair follows what is wrong: repointing where the joints are the problem, a new flaunching where it has failed, fresh lead where the bands have pulled. Repointing a stack is slow, careful work.

1.2 Gables and verges
The gable wall rises to the roof edge, called the verge, and the tiles there are pinned and bedded to the wall. Brick walls of this kind are cut by the weather where the roof overhangs little, so we look for missing bedding, gaps at the top of the wall and tiles that have shifted. Repairs are fixed with clips or nails and bedded neatly, and we match the existing tile as far as we can. A stack and a gable are each a small job on their own. Done together under one scaffold, they spare you paying for access twice. Our chimney repairs page covers the wider range of stack work.
Brick ages differently depending on its firing and where it sits. Soft, older bricks lose their faces first, and a hard cement repoint over them can trap moisture and speed the flaking. So the mortar for repointing an older stack is chosen to be no harder than the brick it joins, and the old joints are raked out to a proper depth instead of being smeared over. Pots and cowls are checked at the same time, since a loose pot can let rain straight down a flue.
Typical UK cost to repoint a chimney stack, by house
| House type | Typical UK range |
|---|---|
| Bungalow | £200 to £700 |
| Semi-detached, side stack | £600 to £900 |
| Semi-detached, central stack | £900 to £1,500 |
| Detached | £700 to £900 |






