Lambeth · Greater London
Extension pulling away repairs in Lambeth
Repairing a separating extension in Lambeth can be as simple as tying the junction or as involved as underpinning. The choice rests on the movement history and the ground, and we confirm a fixed written price once the repair is specified.
Guide price from£750per junction inc VAT

- Postcodes
- SE19, SE21, SE24, SE27, SW2
- Population
- about 320,000
- Area
- Greater London
- Pricing region
- London
Why does the ground in Greater London matter for extension pulling away repairs?
Lambeth is one of the 32 London boroughs, with around 320,000 residents in districts such as SE19, SE21, SE24, SE27, SW2. If you are just outside Lambeth, we also cover Southwark (2 miles), Wandsworth (3 miles) and Westminster (4 miles).
Shrinkable clay is widespread in Greater London. Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Greater London: Victorian and Edwardian terraces with shallow footings, inter-war semis in the outer boroughs, and converted flats and mansion blocks.
Repair options we may recommend
Movement joint and making good
Where some seasonal movement is expected to continue, the junction is formed into a proper flexible movement joint with a compressible filler and sealant, so the two parts can move without cracking. Flashings and internal finishes are detailed to suit.
Best for: Minor ongoing movement that does not threaten the structure
Underpinning the extension
If the extension is still dropping because its footings are too shallow or on poor ground, they are taken deeper by mass concrete, beam-and-base or mini-piles. The engineer designs the scheme, and the junction is repaired once the new foundation is in.
Best for: Active movement from shallow footings, roots or soft ground
What to expect when we carry out extension pulling away repairs
Show us the junction
Send photos of the crack outside, the internal corner and any flashing above, with a measure for scale. We give a free initial assessment and an initial view on whether the gap is likely old or still opening.
Find what is moving
An independent chartered structural engineer can inspect, and we can arrange one. A drain survey under the extension, a trial pit at its footing and tell-tale monitoring across the joint are common checks before choosing the repair.
Choose the fix
The engineer decides between ties, a movement joint or underpinning. We confirm a fixed price in writing once the repair is specified, covering the junction, flashings, internal finishes and any foundation work.
Is it time for extension pulling away repairs? Common signs
- Extension roof flashing lifting off the original wall
- Patio doors or windows in the extension starting to bind
- Daylight or draughts showing through the internal corner joint
What should you budget for extension pulling away repairs in Lambeth?
The ranges below reflect typical London costs for extension pulling away repairs, including VAT. Scaffold, access and making good can push a job to the top of the range.
| Item | Guide price | Per |
|---|---|---|
| Junction crack repair with stainless tiesest. | £750 – £2,500 | per junction |
| Movement joint and making goodest. | £500 – £1,500 | per junction |
| Underpinning the extension where needed | £1,250 – £3,100 | per metre of wall |
Rules for extension pulling away 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.
Your extension pulling away repairs questions
What is the price of extension pulling away repairs in Lambeth?
Guide prices for extension pulling away repairs in Lambeth start from about £750 per junction, including VAT, on London rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you carry out extension pulling away repairs in Lambeth?
We do. Lambeth and the surrounding area are covered, including nearby Southwark and Wandsworth. A free initial assessment from your photos is the first step.
Does the ground around Lambeth cause cracking?
Most of Greater London sits on London Clay, among the most shrinkage-prone ground in the UK, with river gravels along the Thames. Subsidence claims here are among the most frequent in the country, especially after dry summers and near street and garden trees. Only an investigation can say why a particular building has moved.
Can I just fill the gap with mastic?
Mastic can keep water out short term, but it does not stop movement or reconnect the walls. If the gap reopens after filling, something is still moving. Photograph and measure it over a few months first, so an engineer can see the trend.
Who is responsible if a recent extension is moving?
If the extension is recent, the original builder, the designer or building control records may be relevant, and you may have rights against the builder. Gather the plans, completion certificate and contract. Insurance often excludes defects in new construction, so check your policy.
More repairs we carry out in Lambeth
- Resin injection ground stabilisation
- Retaining wall repairs
- Floor joist repairs
- Concrete repairs
- Bowing wall repairs
Extension pulling away repairs near Lambeth
Photos of the crack, the internal corner and the roof flashing are a good start; send them about your Lambeth home and we will reply with a view.