Devon · England
Extension pulling away repairs in Devon
Devon has its own mix of ground and building types, and that shapes how extension pulling away repairs is done here. Most of Devon is on firmer ground than the clay belts of the south-east.
Guide price from£620per junction inc VAT
- Area
- Devon
- Pricing region
- South West
- Ground
- Mostly firmer ground
- Towns listed
- 10
What is the ground like in Devon?
Devon's ground is mostly older mudstones, sandstones and granite, so shrinkable-clay subsidence is less widespread than further east. Older solid-walled and cob buildings, steep sites and retaining walls are the more common structural concerns.
Old metal-mine shafts and workings are recorded in places, so mining searches are routine for some properties. What you mostly find across Devon: cob and stone cottages, Victorian terraces in Exeter, Plymouth and Torbay, and post-war estates.
Methods for extension pulling away repairs
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
From first photo to finished repair
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.
Symptoms that point to extension pulling away repairs
- A vertical crack or gap where the extension meets the house
- Daylight or draughts showing through the internal corner joint
- Patio doors or windows in the extension starting to bind
- Mastic or render at the joint repeatedly splitting open
Guide prices for extension pulling away repairs in Devon
These are guide prices for Devon, 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 |
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.
Extension pulling away repairs near you in Devon
Frequently asked questions
Does the ground around Plymouth cause cracking?
Devon's ground is mostly older mudstones, sandstones and granite, so shrinkable-clay subsidence is less widespread than further east. Older solid-walled and cob buildings, steep sites and retaining walls are the more common structural concerns. Old metal-mine shafts and workings are recorded in places, so mining searches are routine for some properties. Only an investigation on site can say why a particular building has moved.
How much will extension pulling away repairs cost in Devon?
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.
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.
What is a movement joint?
A movement joint is a deliberate, flexible break in a wall that lets two parts of a building move slightly without cracking. It is filled with a compressible material and sealed. At an extension junction it can replace a rigid joint that keeps cracking.
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.