Salisbury · Wiltshire
Extension pulling away repairs in Salisbury
Rear and side extensions are common across Salisbury, and so is the crack where new meets old. Usually it reflects the two parts sitting on different foundations, and the first question is whether the gap is still opening.
Guide price from£620per junction inc VAT

- Postcodes
- SP1, SP2
- Population
- about 45,000
- Area
- Wiltshire
- Pricing region
- South West
Is Wiltshire prone to ground movement?
With roughly 45,000 people, Salisbury spans postcode districts SP1, SP2 in Wiltshire. Nearby, we also cover Romsey (14 miles), Andover (16 miles) and Totton (17 miles).
Wiltshire has a mix of ground, with clay in some places and firmer rock in others. Ground movement here is more often linked to soils, drains and trees than to mining. Typical buildings in Wiltshire: Stone cottages, railway terraces in Swindon, and large post-war and new-build estates.
Is it time for extension pulling away repairs? Common signs
- Extension roof flashing lifting off the original wall
- A vertical crack or gap where the extension meets the house
- Floor level dropping where the extension and house floors meet
What should you budget for extension pulling away repairs in Salisbury?
For Salisbury we use South West rates. Treat the table as a budget guide, inc VAT; the price you pay is the one on your written quote.
| 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 |
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.
Repair the junction
Drains are repaired first if they are leaking. The joint is then tied, formed as a movement joint or rebuilt after underpinning, with roof flashings reset so the junction stays watertight. Building control is handled where needed.
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.
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
How much will extension pulling away repairs cost in Salisbury?
Guide prices for extension pulling away repairs in Salisbury start from about £620 per junction, including VAT, on South West rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you cover Salisbury?
Yes. We take enquiries from across Salisbury, including SP1, SP2, and from nearby places such as Romsey and Andover. Send photos for a free initial view and we will tell you what happens next.
Is the ground in Wiltshire prone to subsidence?
Southern Wiltshire is chalk, while the north around Swindon, Chippenham and Trowbridge sits on Oxford and Kimmeridge Clays that are prone to seasonal movement near trees. Bath stone was mined underground around Corsham. Only an investigation can say why a particular building has moved.
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.
Can a drain under my extension cause it to move?
Yes, a cracked or displaced drain beneath or beside an extension can soften clay or wash away fine soil. A CCTV drain survey usually finds it. Repairing the drain is often the first and most important step before any repair to the walls.
Other structural repairs in Salisbury
- Bay window subsidence repairs
- Structural surveys and crack monitoring
- Bowing wall repairs
- Wall tie replacement
- Subsidence insurance claim repairs
Extension pulling away repairs near Salisbury
If the junction at your Salisbury property keeps reopening, send dated photos and we will suggest whether monitoring, a drain survey or a repair comes next.