Service
Chimney Repointing and Stack Repairs in London & Kent
The most exposed masonry on your house, put back properly: joints raked and repointed, flaunching renewed and weathering details reinstated, with access arranged by us.
Access and scaffolding arranged by us · 10-year workmanship guarantee
- 18 years' experience
- £2m public liability insurance
- 10-year workmanship guarantee
- K Rend approved installer
- Listed on TrustATrader
What chimney repointing covers
A chimney stack takes weather on four sides, from above, and with nothing sheltering it. It is the first masonry on any house to fail and the one people look at last, because it cannot be seen properly from the ground.
The work typically covers raking out and repointing the stack joints in an appropriate mortar, renewing the flaunching, the mortar fillet that beds the pots, repointing or rebedding the pots themselves, checking and repairing the haunching, and making sure the weathering details where the stack meets the roof are doing their job.
Where the top courses have already gone, part of the stack may need taking down and rebuilding rather than repointing. We will tell you which it is on inspection rather than pointing over masonry that needs rebuilding.
Who needs it and when
Any property with a stack, in use or redundant. Redundant stacks are often in the worst condition precisely because nobody thinks about them, and a capped, unused stack still sheds water into the house if the flaunching has cracked.
Triggers: damp staining on a chimney breast in a bedroom or loft, mortar or debris in the fireplace or on the roof, visibly open or washed-out joints seen from a neighbouring window or a drone photo, a leaning stack, cracked flaunching, loose pots, or a survey flagging the stack before a sale.
It is the classic job to combine with roofing work or a full repointing project, because the access is the expensive component and it is already standing.
What happens if it is left
The cost of leaving it another winter
Water entering a stack does not stay at roof level. It runs down the flue and the masonry and appears as staining on the chimney breast in the room below, often accompanied by salting as hygroscopic salts from old soot deposits draw moisture out of the air. Redecorating that breast before the stack is repaired is money spent twice.
Structurally, a stack with washed-out joints is a genuine hazard. Open joints reduce the bedded area on the tallest, most exposed, least supported masonry on the building, and prevailing wind does the rest, leaning stacks and displaced top courses are how this ends.
Cracked flaunching is the other common failure: pots work loose in it, water runs straight into the head of the stack, and a loose pot above a public footway or a neighbour's roof is a liability nobody wants to be reminded of after the event.
Common mistakes we are called in to undo
- Smearing new mortar over washed-out joints from a ladder instead of raking back to sound material with proper access.
- Repairing the flaunching in a thin skim over the cracked existing fillet, which cracks again in one season.
- Repointing a stack that actually needs its top courses rebuilding, so the work fails with the masonry beneath it.
- Treating the internal staining as condensation and redecorating while the stack keeps letting water in.
Our process
How a chimney repointing job runs from first call to guarantee
Step 1
Inspection
We assess the stack at close quarters: joint condition, brick condition, flaunching, pots, haunching, lead or mortar weathering details at the roof line, and whether the stack is plumb.
Step 2
Diagnosis and specification
We decide between repointing, partial rebuild and flaunching renewal, choose the mortar for the exposure and the brick, and issue a written fixed price with a payment schedule.
Step 3
Access
Scaffolding and safe access are arranged by us and priced in the quote, along with roof protection so tiles are not damaged during the work.
Step 4
Repointing and flaunching renewal
Joints are raked to sound material and repointed to a weathered profile, damaged bricks replaced, the old flaunching removed and a new fillet formed to shed water clear of the pots.
Step 5
Verification, protection and guarantee
We check pots are secure, the flaunching falls correctly, debris is cleared from the roof and gutters, and fresh work is protected while it cures. Completed work carries our 10-year workmanship guarantee.
What you get
The results this work is actually bought for
The chimney breast stains stop
Closing the water route at the stack is what ends the recurring damp patch in the bedroom or loft below.
A stack that is safe above head height
Sound joints and secure pots remove a real liability over paths, gardens and neighbouring roofs.
Repointing instead of rebuilding
Catching a stack while the joints are the problem avoids the far larger cost of taking it down and rebuilding it.
Access handled for you
We arrange and price the scaffolding, so there is no separate contractor to book and no surprise access cost later.
Every detail dealt with at once
Joints, flaunching, pots and roof-line weathering are inspected and repaired in the same visit, not one at a time.
Clean for a sale or survey
Stacks are one of the first things surveyors flag. Recently repointed and re-flaunched removes the negotiating point.
In detail
Chimney repointing: materials, methods and where it applies
Mortar and exposure at high level
A stack is the most exposed masonry on the building, so the mix is chosen accordingly. On period stacks in soft brick that usually means a hydraulic lime at an appropriate designation rather than the weakest option; on modern brick a cement-lime-sand mix is appropriate. Weatherstruck profiles are common up here because they throw water clear of the joint.
Flaunching is formed as a solid fillet with a proper fall from the pots to the outside edge, not a flat cap that ponds. Where pots are loose, they are rebedded as part of the same operation rather than relied on to hold themselves in place in fresh mortar.
Variations: repoint, part-rebuild, full rebuild
Repointing suits a stack whose bricks are sound and joints are worn. A partial rebuild, usually the top courses above the roof line, is needed where frost and saturation have destroyed the brick faces and the masonry no longer holds a joint. A full rebuild from the roof line up is for leaning or badly degraded stacks.
Redundant stacks bring their own choices: capping while retaining ventilation to the flue, so the stack stays dry inside instead of being sealed with moisture in it, and keeping the flaunching and weathering sound even though the flue is no longer used.
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Weathering details at the roof line
Where the stack passes through the roof is a frequent leak point independent of the pointing: failed cement fillets instead of proper lead flashings and soakers, lead that has slipped out of its chase, or an unsealed back gutter behind the stack. These are inspected as part of the assessment because repointing a stack above a failed flashing will not stop a leak.
We are repointing and rendering specialists, where a repair is genuinely roofing or leadwork, we tell you that plainly rather than filling it with mortar and calling it resolved.
Houses, flats and shared stacks
Terraced properties across south-east London frequently have shared stacks straddling a party wall, which means agreeing scope and access with a neighbour. Doing the whole stack at once is almost always cheaper for both parties than two separate scaffolds.
We work across London and Kent, including Bexley, Bexleyheath, Sidcup, Dartford, Erith, Bromley and Orpington, on both domestic and managed property.
Not sure this is the right specification for your wall? See all of our services, the areas we cover, or go back to the homepage.
FAQs
Chimney repointing questions we are asked most
How much does chimney repointing cost?
Access is a significant part of it, along with the stack size and whether the flaunching and pots need renewal. We give a written fixed price including scaffolding after inspection, with payments spread across the project. Quotes are free. Small jobs carry a minimum charge.
How long does a chimney job take?
The masonry work is usually short once access is up; the scaffolding period is generally the longer part. We confirm the programme in writing with your quote.
Do you arrange the scaffolding?
Yes. Access and scaffolding are arranged by us and included in the written quote rather than added later.
How do I know my chimney needs repointing?
Damp staining on the chimney breast or in the loft, mortar debris in the fireplace or gutters, visibly washed-out joints, cracked flaunching, loose pots or a stack that is no longer plumb.
Should a redundant chimney be removed or repaired?
Repair and cap with ventilation is usually the better option, it keeps the roof line and the property's character intact and costs less than removal and making good. Sealing a flue with no ventilation traps moisture, so it is done properly or not at all.
What is flaunching and why does it matter?
It is the sloped mortar fillet on top of the stack that beds the pots and sheds water clear. When it cracks, water runs straight into the head of the stack and down into the house, and pots start to work loose.
How long does chimney repointing last?
At high level, exposure is the driver. Correctly specified and compacted pointing with sound flaunching is a long-cycle job, but a stack will always weather faster than the walls below it.
Is the work guaranteed?
Yes: 10-year workmanship guarantee on completed work, £2 million public liability insurance, and we are listed on TrustATrader.
Can you do urgent work on a loose pot or damaged stack?
Contact us on 07360 597865 between 8am and 5pm. Genuinely unsafe masonry is prioritised where our programme and access allow, but access has to be arranged before anyone works at that height.
Related work
Often carried out alongside this
Brickwork repointing & repair
Raking out tired joints, replacing spalled bricks and repointing to a clean, consistent line.
Read moreHydraulic lime repointing
Breathable lime mortar joints for period and solid-wall brickwork, matched to the original pointing style.
Read moreExterior damp specialists
We trace penetrating damp back to the failed pointing, render or detail causing it, then put the fabric right.
Read moreFree quote
Sort the stack before it becomes a rebuild
Tell us what you are seeing, staining on the breast, debris, a leaning stack, and we will inspect it properly, arrange the access and give you one written price covering the lot.
- 18 years' experience
- £2m public liability insurance
- 10-year workmanship guarantee
- K Rend approved installer
- Listed on TrustATrader