Chapter one
Brickworks, clay country and Plumpton Green chimneys
A parish that fired its own bricks has plenty of brick stacks, and the leaks often start where stack meets slope.
The Victoria County History records that large quantities of bricks were made in the north of Plumpton parish when it was written in 1940, and the village itself lies in the Low Weald, the clay country below the Downs. What covers your roof stays an open question until someone has been up to look at it. What we can say in advance is that houses with brick walls usually carry brick chimney stacks, and a stack is a gap in the roof surface that has to be sealed on every face. When a Plumpton Green ceiling starts to stain, the stack is the first place a ladder goes. Brick also tells you something about the age of the fixings around it: lead, mortar and nails bedded into a stack have often been there a long time before anyone checks them.
At a glance
- Bricks were made in the north of the parish
- Flashings and pointing fail before the brick does
- Chimney repointing runs from £500 to £2,000 nationally
1.1 Where a stack lets water in
Four faults turn up again and again. Mortar between the bricks erodes and leaves open joints. The flashing, a strip of lead dressed from slope to brickwork, lifts or splits. The cap of sloped mortar around the pots, called flaunching, cracks and lets rain run behind it. Or the back gutter, the trough behind the stack where the slope drains round it, silts up with moss and grit. Each produces damp that travels along the timber and appears somewhere else, often in a bedroom corner well away from the chimney. We follow the damp back to its start before quoting, and our chimney repairs page sets repointing beside rebuilding.
1.2 Lead, pointing or rebuild
If the brick is sound and the joints are open, repointing is usually the answer. If the lead has split, new lead is dressed into the joints and held with wedges, which is work we describe on our lead roofing page. A stack that leans or has lost courses needs a rebuild, and removing a chimney breast altogether is a separate matter that always involves Building Regulations approval, with a party wall notice where it adjoins a neighbour. National guides give a feel for the spread of cost, set out in the table below, and each figure depends on the height of the stack, the access and how much brick has to come down. Scaffold or a tower is often the largest single item on a tall stack, so ask any firm whether it is included. We write up one total once the survey is finished.
Typical UK chimney repointing by property type
| Property | 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 |
