Portsmouth · Hampshire
Chimney stack repairs in Portsmouth
Before repairing a stack at a Portsmouth property, we ask what lies beneath it. If a chimney breast has been removed inside, the support for the stack above needs checking by an engineer before any work on the roof.
Guide price from£560per stack inc VAT

- Postcodes
- PO1, PO2, PO5
- Population
- about 210,000
- Area
- Hampshire
- Pricing region
- South East
What is the ground like in Hampshire?
Portsmouth is in Hampshire and takes in postcode districts PO1, PO2, PO5. About 210,000 people live there. Neighbouring towns we cover: Fareham (5 miles), Hayling Island (5 miles) and Havant (6 miles).
Hampshire is one of the parts of the UK where clay soils are most likely to move with the seasons. Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Hampshire: Victorian terraces in Portsmouth and Southampton, 1930s semis, and large post-war and new-build estates.
What to look for before calling about chimney stack repairs
- Chimney pots that are loose, tilted or cracked at the base
- Mortar washed out of joints, leaving bricks standing proud
- Damp patches on the chimney breast inside, especially after rain
Chimney stack repairs prices in Portsmouth
Prices in Portsmouth are worked out on South East rates. They include VAT and are a starting point: access, the extent of the damage and whether an engineer or building control is involved all move the figure.
| Item | Guide price | Per |
|---|---|---|
| Repointing, flaunching and minor brick repairs | £560 – £2,250 | per stack |
| Partial or full stack rebuild | £3,350 – £11,200 | per stack |
| Stack restraint or strappingest. | £450 – £1,350 | per stack |
How we usually approach chimney stack repairs
Flaunching and pot resetting
Old cracked flaunching is broken out, pots are lifted and reset or replaced, and new flaunching is formed to a fall so water runs off. Unused flues can be capped with ventilated caps, which keeps rain out while letting the flue breathe.
Best for: Loose pots and cracked mortar at the top of the stack
Repointing and brick repairs
Eroded joints are raked out and repointed in a mortar suited to the brick, often a lime-based mix on older stacks. Spalled or cracked bricks are cut out and replaced with matched reclaimed or new bricks. On many stacks this, with new flaunching, is all that is needed.
Best for: Upright stacks with weathered joints and some damaged bricks
What happens during chimney stack repairs, step by step?
Check what is below
We ask whether any chimney breasts have been removed, and check the loft and rooms below for cracking. If a breast has gone without proper support, we recommend an independent chartered structural engineer before any stack work.
Scaffold to the stack
Safe access is set up with a working platform around the stack. On terraces we may need to agree access over a neighbour’s roof, and a council licence is arranged where the scaffold stands on the pavement.
Weatherproof and clear
Caps or cowls are fitted where agreed, the roof around the stack is checked for slipped tiles, and debris is cleared from gutters. You receive photos of the finished stack taken from the scaffold, since it is hard to see from the ground.
Rules for chimney stack repairs in England
In England, underpinning and other work that alters or strengthens a wall or foundation is building work under the Building Regulations (Part A, structure), so building control approves and inspects it. Like-for-like repairs often are not, and we tell you which applies before a price is agreed. Work to a party wall, or excavation close to a neighbour’s foundations, can also need a notice under the Party Wall etc. Act 1996.
Questions about chimney stack repairs in Portsmouth
How much should I budget for chimney stack repairs in Portsmouth?
Guide prices for chimney stack repairs in Portsmouth start from about £560 per stack, including VAT, on South East rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Can you survey a property in Portsmouth?
We do. Portsmouth and the surrounding area are covered, including nearby Fareham and Hayling Island. A free initial assessment from your photos is the first step.
Why do houses in Hampshire crack?
Central Hampshire is chalk, while the south around Portsmouth, Southampton and the New Forest fringe and the north-east around Farnborough sit on London Clay, Reading Beds and other clays and sands. The clay areas see seasonal movement near trees. Only an investigation can say why a particular building has moved.
Can a leaning stack be straightened?
Not by pushing it back, because the brickwork would crack. A slight lean on a sound stack can be restrained so it moves no further. A pronounced lean is fixed by taking the stack down to sound masonry and rebuilding it plumb.
What if a chimney breast below has been removed?
Where the breast has gone but the stack is still on the roof, how that stack is now held up is a structural question. Cracking in nearby ceilings or a dropped stack are warning signs. An independent chartered structural engineer should assess it before any repair, and we can arrange one.
Related work in Portsmouth
- Resin injection ground stabilisation
- Lintel replacement
- Floor joist repairs
- Extension pulling away repairs
- Gable end wall repairs
Chimney stack repairs near Portsmouth
Sharing a stack with next door in Portsmouth? We can quote for the whole stack so you and your neighbour can see the full picture.