Somerset · England
Extension pulling away repairs in Somerset
Extension pulling away repairs in Somerset starts with the ground. Clay soils are found in parts of Somerset, and the buildings here are mostly Bath stone Georgian terraces, so the repair has to suit both.
Guide price from£620per junction inc VAT

- Area
- Somerset
- Pricing region
- South West
- Ground
- Clay in parts
- Towns listed
- 11
How do local ground conditions affect extension pulling away repairs in Somerset?
Somerset mixes Lias clays, Mercia Mudstone, limestone hills and the peat and alluvium of the Levels around Bridgwater, which can settle. The former Somerset coalfield around Radstock and Midsomer Norton left recorded workings.
Parts of Somerset lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Typical buildings in Somerset: Bath stone Georgian terraces, Victorian houses in Taunton and Weston-super-Mare, and post-war estates.
What happens when we carry out extension pulling away repairs in Somerset?
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.
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.
Finish and hand over
Internal corners are replastered, skirtings and coving refixed, and doors or windows in the extension eased where the movement affected them. Records of the repair and any approvals are passed to you.
Signs you may need extension pulling away repairs
- Daylight or draughts showing through the internal corner joint
- Patio doors or windows in the extension starting to bind
- Floor level dropping where the extension and house floors meet
- A vertical crack or gap where the extension meets the house
How much will extension pulling away repairs cost in Somerset?
These are guide prices for Somerset, using South West rates and including VAT. Your written quote follows photos or a survey, and is fixed once the repair is specified.
| Item | Guide price | Per |
|---|---|---|
| Junction crack repair with stainless tiesest. | £620 – £2,050 | per junction |
| Movement joint and making goodest. | £410 – £1,250 | per junction |
| Underpinning the extension where needed | £1,050 – £2,600 | per metre of wall |
Which repair method suits a home in Somerset?
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
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
Junction crack repair with stainless ties
The open joint is cut out, stainless ties or helical bars are fixed across it into both the old and new masonry, and the joint is repointed or rendered to match. Inside, the corner is replastered. This suits extensions that moved once and have since stopped.
Best for: Settled extensions with a stable gap at the junction
Do you need approval 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.
Towns in Somerset we cover for extension pulling away repairs
Extension pulling away repairs in Somerset: questions and answers
Is the ground in Somerset prone to subsidence?
Somerset mixes Lias clays, Mercia Mudstone, limestone hills and the peat and alluvium of the Levels around Bridgwater, which can settle. The former Somerset coalfield around Radstock and Midsomer Norton left recorded workings. Parts of Somerset lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Only an investigation on site can say why a particular building has moved.
How much will extension pulling away repairs cost in Somerset?
On South West rates, extension pulling away repairs starts from about £620 per junction, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Will my extension need underpinning?
Often not. Many separating extensions are fixed by repairing a drain, tying the junction or forming a movement joint. Underpinning is for extensions that keep dropping because their footings are too shallow or the ground beneath is poor, as shown by monitoring.
Why is my extension pulling away from my house?
Usually because the extension and the house sit on different foundations that react differently to the ground. Shallow extension footings, leaking drains under the extension, nearby roots and weak tie-ins between old and new walls are the common causes.
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.