Mid Glamorgan · Wales
Extension pulling away repairs in Mid Glamorgan
Across Mid Glamorgan, requests for extension pulling away repairs usually begin with a crack someone has noticed getting wider. Mid Glamorgan has a mix of ground, with clay in some places and firmer rock in others. A repair only lasts if the reason for the movement has stopped.
Guide price from£550per junction inc VAT

- Area
- Mid Glamorgan
- Pricing region
- Wales
- Ground
- Clay in parts
- Towns listed
- 12
What is the ground like in Mid Glamorgan?
Mid Glamorgan lies on the South Wales coalfield, with dense historic workings, spoil tips and steep valley sides. Landslip, retaining walls and mining legacy are all live issues in the valleys.
Historic coal workings are recorded beneath parts of Mid Glamorgan, and a coal mining search is worth checking where movement is unexplained. Across Mid Glamorgan, most homes are long stone and brick terraces on valley sides, Victorian houses in Bridgend and post-war estates.
Repair options we may recommend
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
What to expect when we carry out extension pulling away repairs
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.
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.
Is it time for extension pulling away repairs? Common signs
- Floor level dropping where the extension and house floors meet
- 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
What should you budget for extension pulling away repairs in Mid Glamorgan?
Guide prices below are for homes in Mid Glamorgan, on Wales rates and including VAT. A survey or good photos let us turn them into a fixed written price.
| Item | Guide price | Per |
|---|---|---|
| Junction crack repair with stainless tiesest. | £550 – £1,850 | per junction |
| Movement joint and making goodest. | £370 – £1,100 | per junction |
| Underpinning the extension where needed | £920 – £2,300 | per metre of wall |
Do you need approval for extension pulling away repairs in Wales?
In Wales, the Welsh version of the Building Regulations applies. Underpinning and other work that alters or strengthens the structure needs building control approval and inspection; like-for-like repairs often do not. The Party Wall etc. Act 1996 applies to work on party walls and excavation close to a neighbour’s foundations.
Extension pulling away repairs near you in Mid Glamorgan
- Rhondda
- Tonypandy
- Bridgend
- Merthyr Tydfil
- Pontypridd
- Aberdare
- Caerphilly
- Maesteg
- Porthcawl
- Llantrisant
- Nelson
- Mountain Ash
Your extension pulling away repairs questions
Does the ground around Rhondda cause cracking?
Mid Glamorgan lies on the South Wales coalfield, with dense historic workings, spoil tips and steep valley sides. Landslip, retaining walls and mining legacy are all live issues in the valleys. Historic coal workings are recorded beneath parts of Mid Glamorgan, and a coal mining search is worth checking where movement is unexplained. Only an investigation on site can say why a particular building has moved.
How much will extension pulling away repairs cost in Mid Glamorgan?
On Wales rates, extension pulling away repairs starts from about £550 per junction, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
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.
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.
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.