A chimney stack is exposed on all four sides and takes more weather than any other part of a house. When one starts letting water in, the damp usually appears in a bedroom ceiling or on a chimney breast and gets blamed on the roof covering. We repair, repoint, re-flash, rebuild, cap and remove chimney stacks throughout Mansfield and Nottinghamshire.
Repointing and flaunching
Mortar joints on an exposed stack weather far faster than those on a sheltered wall, and once they are open the brickwork soaks up water that then makes its way down inside the stack. Repointing rakes the failed joints out to a proper depth and fills them with a mortar mix suited to the brick — soft lime-based mixes on older soft bricks, because a hard modern cement mortar will simply push the face off them over a few frosts. The flaunching, which is the sloped mortar bed holding the pots in, cracks for the same reasons and is renewed at the same time.
Lead flashing at the roof line
Where the stack passes through the roof it is weathered with lead — an apron at the front, soakers and step flashing up the sides, and a back gutter behind. This is where most chimney leaks actually originate, usually because the lead was cement-filleted instead of being properly chased into the joints, or because the back gutter is too shallow to cope with the water shedding off the roof above it. We renew stack flashing in code-appropriate lead, chased and wedged into the brickwork, not stuck on with mortar.
Capping and removal
A chimney that is no longer used does not need to keep letting weather in, but it does need to keep breathing. Capping with a ventilated cowl or a capping slab keeps rain out while letting the flue ventilate, which prevents damp appearing in the chimney breast. If a stack is beyond economic repair or simply unwanted, we can take it down to below the roof line and make the roof good over it, or remove it entirely and re-cover the area to match.
What is included
- Repointing in lime or cement mortar to suit the brickwork
- New flaunching and pot re-bedding
- Lead apron, soaker, step flashing and back gutters
- Partial and full stack rebuilds
- Ventilated capping for disused flues
- Stack removal and roof made good
What it costs, roughly
We quote a fixed price in writing after looking at the job, because roofs vary far more than price lists admit. That said, people reasonably want a ballpark before they pick up the phone, so our roofing price guide sets out real indicative figures for every service we offer, including this one. No registration, no "prices from" that nobody has ever actually paid.