Cambridgeshire · England
Extension pulling away repairs in Cambridgeshire
We arrange surveys and price extension pulling away repairs throughout Cambridgeshire. Cambridgeshire is one of the parts of the UK where clay soils are most likely to move with the seasons, and we take that into account before recommending a method.
Guide price from£630per junction inc VAT
- Area
- Cambridgeshire
- Pricing region
- East of England
- Ground
- Shrinkable clay widespread
- Towns listed
- 8
What should you know about the ground under Cambridgeshire?
Gault Clay underlies much of the Cambridge area and Oxford Clay the west of the county around Peterborough and Huntingdon, while the northern fens are peat and silt that can shrink as they dry. Both clay and peat ground can move with the seasons.
Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Cambridgeshire: Victorian terraces in Cambridge and Peterborough, fen-edge cottages, and extensive post-war and new-build estates.
Symptoms that point to extension pulling away repairs
- A vertical crack or gap where the extension meets the house
- Mastic or render at the joint repeatedly splitting open
- Daylight or draughts showing through the internal corner joint
- Floor level dropping where the extension and house floors meet
Guide prices for extension pulling away repairs in Cambridgeshire
Prices in Cambridgeshire are worked out on East of England 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 |
|---|---|---|
| Junction crack repair with stainless tiesest. | £630 – £2,100 | per junction |
| Movement joint and making goodest. | £420 – £1,250 | per junction |
| Underpinning the extension where needed | £1,050 – £2,600 | per metre of wall |
Methods for extension pulling away repairs
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
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
From first photo to finished repair
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.
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.
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 Cambridgeshire we cover for extension pulling away repairs
Frequently asked questions
Is the ground in Cambridgeshire prone to subsidence?
Gault Clay underlies much of the Cambridge area and Oxford Clay the west of the county around Peterborough and Huntingdon, while the northern fens are peat and silt that can shrink as they dry. Both clay and peat ground can move with the seasons. Ground movement here is more often linked to soils, drains and trees than to mining. Only an investigation on site can say why a particular building has moved.
How much will extension pulling away repairs cost in Cambridgeshire?
On East of England rates, extension pulling away repairs starts from about £630 per junction, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Is it normal for an extension to crack at the join?
A fine crack at the junction is fairly common, especially in the first few years as a new extension settles. It becomes a concern when the gap is widening, tapering, letting in water or matched by sticking doors and sloping floors. Those signs point to continuing movement.
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.
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.