Chimney Repairs In Dartford
Is your chimney the reason the bedroom wall is damp?
Repointing, flaunching, lead, pots and cowls, and taking down stacks you no longer use
Chimney repairs in Dartford often involve two households. On a terrace or a pair of semis, one stack usually serves both homes, with the party wall running straight up through the middle of it. So when the mortar crumbles or the flaunching cracks, the problem belongs to both of you. Stacks are also the most exposed brickwork on any house. They catch wind from every side, they get soaked and then frozen, and the lead where they meet the roof is one of the most common leak points we find on a survey. We repoint, rebuild loose tops, renew flaunching and lead, fit pots and cowls, and take down stacks nobody needs any more. The survey and written quote are free.
Ask for a chimney survey
A roofer rings you back to arrange a visit.
What a properly repaired chimney does for your house
Chimneys fail slowly and then all at once. Catch them early and the work is modest. Here's what repair gets you.
01
Dry walls beside the breast
Damp patches on an upstairs chimney breast usually mean water getting in at the top or at the flashing. Fix those and the stain stops spreading. Leave them and the plaster eventually blows, and that's a second bill on top of the first.
02
No bricks on the path
Loose bricks and a cracked crown are a hazard over a front path, a car or your neighbour's conservatory. Repointing and rebuilding the top few courses puts strength back where the weather has taken it out.
03
One scaffold, both sides done
On a shared stack we'll quote both owners if you want, so the whole chimney is repaired from a single scaffold. Repairing half a stack leaves the other half free to let water in and down the party wall.
04
Pots and cowls that suit the flue
Open fire, gas, wood burner or nothing at all? Each needs a different top. A capped flue still needs to breathe, or condensation builds up inside. We fit what matches how each flue is really used.
05
Fresh lead where water gets in
Stepped flashings up the sides, an apron across the front, a back gutter behind the stack. When any of those lifts or splits, water runs straight into the roof void. New lead is dressed to the brickwork and wedged into the mortar joints.
06
Removal, when it's the better answer
A redundant stack that leaks every winter can come down below roof level, with the hole tiled over and the leak gone for good. Where the stack is shared, your neighbour has to agree, and we'll explain what it involves before anything is booked.
1,000+
Roofs repaired, renewed and rebuilt
10 yrs
Written guarantee on every re-roof
5★
The only rating anyone has left us
£0
For the survey and the written quote
Shared stacks on Dartford terraces and semis
In a town where most homes are terraced or semi-detached, the chimney is often the one part of the roof that belongs to two people at once. The party wall runs up the middle. You own your half, your neighbour owns theirs, and the weather doesn't care where the line is. If the crown cracks on their side, water can still track across and show up on your chimney breast. That's why we look at the whole stack, even when you've only asked about your half, and tell you plainly where the fault sits.
Exposure matters as well. A stack standing proud of the ridge on an interwar semi near Dartford Heath catches wind from every direction, with no shelter around it. The Great Storm of October 1987 hit Kent and London about as hard as anywhere in Britain, and named storms since, Eunice in 2022 among them, keep testing the same brickwork. Mortar on a chimney has a harder life than mortar anywhere else on the house, and it usually needs repointing long before the walls below it do.
"Most of the damp chimney breasts we're asked to look at in Dartford trace back to a split back gutter or cracked flaunching, not to the bricks themselves."
How we repair a chimney in Dartford
- 1
Look at the whole stack
From the ground with binoculars first, then up close from the roof. We check the crown, flaunching, pots, pointing and every piece of lead, and look at the chimney breast indoors. On a shared stack, we check both sides.
- 2
Written quote, split if shared
You get a written price for the work, the lead, any pots or cowls and the scaffold, with VAT shown. Where the stack is shared, we can lay the quote out so the cost divides fairly between the two households.
- 3
Scaffold round the stack
Chimney work needs a working platform round the stack, not a ladder propped against it. That's usually a chimney scaffold set on the roof, with access from the front or back of the house. Roof tiles below it are protected.
- 4
Remove what's failed
Loose pointing is raked out to a sound depth, cracked flaunching is broken off and tired lead is lifted. Any loose bricks at the top are taken down and set aside, or swapped for matching bricks if their faces have blown.
- 5
Rebuild and repoint
Bricks are re-laid, joints repointed in a mortar that suits the brick, and the top finished with new flaunching shaped to shed water. Pots are bedded firmly, with cowls or vented caps fitted where they're needed.
- 6
Dress new lead
Code 4 or Code 5 lead for the flashings, back gutter and front apron, each piece cut to a sensible length and wedged into the joints. Sealant has its place, but never as a substitute for properly dressed lead.
- 7
Check, photograph, clear up
We go over everything from the scaffold with you, or show you photos if you'd rather stay on the ground. Debris leaves with us, and the scaffold only comes down once you're happy with what you've seen.
10
Years' cover on a new roof
1,000+
Roofing jobs finished
Paperwork in your hand on the last day. Not posted out "in due course".
What the 10 year guarantee on a re-roof actually covers
Re-roof a house in Dartford with us and you get 10 years of cover on the workmanship. It's a written document. It has your address on it, lists what was done, and is dated the day the roof is signed off. If water gets in because something was fitted wrong - a batten, a fixing, a lap, a flashing - a roofer comes back and puts it right. You don't pay for that.
Why are we happy to promise ten years? Because of how the roof goes on. Every tile or slate is mechanically fixed to BS 5534, the current British Standard. Ridges and hips are fixed too, not just sat in mortar. A breathable membrane goes down first. Where a roof meets a wall, a chimney or the house next door, it gets proper lead or a tested dry system. Shortcuts there are what make a guarantee expensive, so we don't take them.
Tiles, slates and membranes also carry the maker's own warranty. Those vary by product, and your paperwork tells you which ones apply. If a job is too unusual to guarantee in the normal way, you'll hear that at quote stage.
Signs of a good chimney roofer in Dartford
They price a scaffold, not a ladder and a bucket
Proper chimney work can't be done safely while leaning off a roof ladder. A roofer who quotes to repoint or re-lead a stack without scaffold is either cutting corners on safety or planning a quick smear of mortar rather than a full rake-out. The scaffold costs money, yes. It's also the only way anyone can do careful work at the top of a stack.
They understand lead
Chimney leaks are mostly lead failures. A good roofer knows the difference between a step flashing and a back gutter, why lead is cut to limited lengths so it can expand without tearing, and how to wedge it into a brick joint instead of sticking it to the face. If a quote says 'seal around chimney with flashing tape', that isn't a repair you want to pay for.
They ask what the flue is for
Before fitting a pot, cap or cowl, a good chimney roofer asks whether you light the fire, whether a gas appliance or stove uses the flue, and what's going on with the other side of a shared stack. Capping a flue your neighbour still uses would be a dangerous mistake. So would fitting the wrong type of cowl on a gas flue. If they don't ask, they probably don't know.
Repoint, rebuild, re-lead or remove?
Most chimney problems end up with one of four fixes. Here's how they differ in scope, cost and who needs to agree.
| Comparison point | Repointing | Rebuild top courses | New lead flashings | Remove the stack |
|---|---|---|---|---|
| What's involved | Rake out and refill the mortar joints | Re-lay loose brickwork, new flaunching | New step flashings, apron and back gutter | Take down below roof line, tile over |
| Typical cost | £650 - £1,900 | Priced after survey, usually above repointing | £450 - £1,300 | £1,200 - £2,800 |
| Time on site | One to two days plus scaffold | Two to three days | About a day | Two to three days |
| When it makes sense | Sound bricks, worn joints | Loose, cracked or leaning top | Damp at the breast, brickwork sound | Unused flue with repeat leaks |
| Neighbour involved? | Yes, if the stack is shared | Yes, on a shared stack | Sometimes, if lead spans both sides | Agreement needed on a shared stack |
| Planning | Not needed for like-for-like | Not needed if it matches | Not needed | Check first if listed or in a conservation area |
Pots, cowls and caps, matched to the flue
Chimney tops vary more than people think. A flue serving an open fire needs a clear pot. A disused flue should be capped but still ventilated, with an air brick or vent lower down, or condensation soaks the breast from the inside. Gas appliances need cowls designed for gas. Wood burners normally run through a lined flue with a terminal to match.
If it's the lead around your stack that's failing rather than the brickwork, our leadwork page goes into flashings and back gutters in more detail.
Chimney lead and flashings
Chimney repair prices in Dartford
Repointing a typical stack costs £650 to £1,900, depending on its height and how much is loose. New lead flashings are usually £450 to £1,300. Taking down a redundant stack and tiling over runs around £1,200 to £2,800. Shared stacks often work out cheaper per household when both sides are done together.
Chimney questions from Dartford households
Do I need permission from Dartford Borough Council to remove a chimney?
For most houses, taking down a chimney stack is outside planning control. Listed buildings aren't, because removing or altering a stack needs listed building consent. For a house in the town's single conservation area, around the Town Centre, or at one of the West Hill addresses with an Article 4 direction, check with Dartford Borough Council first. Removing the chimney breast inside is a separate matter and needs building regulations approval for the structural support.
Who pays to repair a shared chimney stack?
Usually both owners, split by agreement, since each of you owns your half. Your deeds may say more. If only one side needs work you can repair your half alone, but on a stack the problem rarely respects the line. The Party Wall etc. Act 1996 can apply to work on the party wall, including the part running up through a shared stack, so take advice if your neighbour objects.
What is flaunching, and why does it crack?
Flaunching is the sloped mortar cap around the pots at the very top of the stack. It holds the pots in place and throws water off the top. Being fully exposed, it takes frost, sun and wind harder than any other mortar on the house. Once it cracks, water gets into the top of the stack and soaks down. Renewing it is a common and fairly quick repair.
Should I cap a chimney I don't use?
Yes, but cap it properly. A capped flue needs airflow, usually a vented cap at the top and an air brick or vent into the room at the bottom. Seal both ends tight and moisture trapped inside shows up as damp patches on the breast. If you might want a fire again one day, a removable cap keeps that option open.
My chimney is leaning. Is it dangerous?
It can be. A lean often comes from sulphate attack, where flue gases have soaked into the mortar on one side over many years and made it expand. Long-term weathering on the exposed face can do it too. Some leans are old and stable. Others are getting worse. Keep people away from underneath and get it looked at soon. We'll tell you whether it needs taking down and rebuilding.
Can you repair a chimney without scaffolding?
Small jobs, like rebedding a single pot on a low bungalow stack, can sometimes be done from a roof ladder. Anything involving repointing, rebuilding or new lead needs a working platform round the stack. It's the only way to do the work safely and properly, so we include it in the quote from the start instead of springing it on you later.
Related: Leadwork · Roof repairs · Re-roofing · Emergency roof repairs
Reviews from Dartford homeowners
Every review left for us so far has been five stars. We're adding them here as they come in.
Reviews only tell you so much anyway. When a roofer comes out to Dartford, ask to see photos of a recent job on a house like yours. A good roofer will have plenty and won't mind you asking.
Chimney work across Dartford and the surrounding towns
Damp breast or a tired-looking stack?
Book a free survey. We'll check the whole chimney, both sides if it's shared, and send a written price with photos of exactly what we found up there.