West Glamorgan · Wales
Subsidence repairs in West Glamorgan
We carry out subsidence repairs across West Glamorgan, from the larger towns to smaller places nearby. West Glamorgan has a mix of ground, with clay in some places and firmer rock in others. Every job starts with the cause, then the repair is specified to match it.
Guide price from£2,300per property inc VAT

- Area
- West Glamorgan
- Pricing region
- Wales
- Ground
- Clay in parts
- Towns listed
- 4
How do local ground conditions affect subsidence repairs in West Glamorgan?
Swansea and Neath Port Talbot lie on the South Wales coalfield, with historic workings, tips and steep valley sides, and softer estuarine ground around the docks.
Historic coal workings are recorded beneath parts of West Glamorgan, and a coal mining search is worth checking where movement is unexplained. Across West Glamorgan, most homes are hillside terraces, Victorian villas in Swansea and post-war estates.
Is it time for subsidence repairs? Common signs
- Doors and windows that start to stick or no longer close
- Diagonal cracks wider at the top, running from window or door corners
- Fresh cracks showing on both the inside and outside of one wall
- Cracks that open in summer and partly close again in winter
What should you budget for subsidence repairs in West Glamorgan?
Prices in West Glamorgan are worked out on Wales 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 |
|---|---|---|
| Structural engineer's investigation and report | £460 – £1,850 | per property |
| CCTV drain survey (common first check) | £140 – £320 | per survey |
| Typical repair once the cause is dealt with: crack stitching and making goodest. | £2,300 – £11,000 | per property |
| Foundation strengthening where it is needed (see underpinning) | £920 – £3,200 | per metre of wall |
Repair options we may recommend
Foundation strengthening
Where the ground cannot be made stable, the load is carried down to firmer soil by underpinning, a beam-and-base scheme, mini-piles or resin injection, depending on the soil and access. It is designed by an engineer and is the exception, not the rule.
Best for: Ongoing movement where removing the cause has not worked
Remove the cause, then repair
Most subsidence is dealt with this way. The drain is repaired or the vegetation managed, the house is watched to confirm it has stabilised, and then the cracks are stitched, repointed and made good inside. It is the least disruptive route and usually the cheapest.
Best for: Clay movement or drain leaks where the cause can be removed
Crack stitching and making good
Once movement has stopped, cracked brickwork is cut along the bed joints, stainless helical bars are bonded in to tie the wall together, and the joints are repointed to match. Inside, plaster is renewed along the crack line before redecoration.
Best for: Category 1 to 3 cracking in walls that are otherwise sound
What to expect when we carry out subsidence repairs
Send photos or call
Send photos of the cracks with a coin or tape for scale, and say when you first noticed them. We give a free initial assessment and suggest whether an engineer, a drain survey or your insurer comes first.
Written quote
We price the agreed repair and confirm a fixed price in writing once it is specified. If there is an insurance claim, we can price to the loss adjuster’s or engineer’s schedule instead of our own scope.
Repairs and making good
Cracks are stitched and repointed outside, plaster is renewed along the crack lines inside, and sticking doors are eased. Where the work needs it, we deal with building control and hand over the paperwork.
Do you need approval for subsidence 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.
Subsidence repairs near you in West Glamorgan
Your subsidence repairs questions
Does the ground around Swansea cause cracking?
Swansea and Neath Port Talbot lie on the South Wales coalfield, with historic workings, tips and steep valley sides, and softer estuarine ground around the docks. Historic coal workings are recorded beneath parts of West 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 subsidence repairs cost in West Glamorgan?
On Wales rates, subsidence repairs starts from about £2,300 per property, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Does subsidence always need underpinning?
No, most subsidence is repaired without underpinning. When a leaking drain is fixed or nearby vegetation is managed, the ground usually stabilises and the house needs only crack repairs. Foundation work is kept for movement that continues after the cause has gone.
Can I sell a house that has had subsidence?
Yes, though buyers and lenders will want paperwork. Keep the engineer’s report, monitoring results, the repair specification and any building control sign-off. A repaired house shown to be stable is far easier to sell than one with an open problem.
How do I know if cracks are subsidence?
Subsidence cracks are usually tapered, run diagonally from door and window corners, and show on both faces of the wall. Fine vertical cracks in new plaster are more often shrinkage. An engineer’s inspection, sometimes with monitoring, is the reliable way to tell.