Gwent · Wales
Subsidence repairs in Gwent
Subsidence repairs in Gwent starts with the ground. Parts of Gwent have clay that can shrink near trees in dry spells, and the buildings here are mostly valley terraces on steep hillsides, so the repair has to suit both.
Guide price from£2,300per property inc VAT
- Area
- Gwent
- Pricing region
- Wales
- Ground
- Clay in parts
- Towns listed
- 11
Is Gwent prone to ground movement?
The valleys of Blaenau Gwent, Torfaen and Islwyn lie on the South Wales coalfield with extensive historic workings and spoil tips, while Newport and Monmouthshire have Mercia Mudstone, alluvium and Old Red Sandstone.
Historic coal workings are recorded beneath parts of Gwent, and a coal mining search is worth checking where movement is unexplained. Housing stock in Gwent: Valley terraces on steep hillsides, Victorian houses in Newport and Abergavenny, and post-war estates.
How much will subsidence repairs cost in Gwent?
These are guide prices for Gwent, using Wales rates and including VAT. Your written quote follows photos or a survey, and is fixed once the repair is specified.
| 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 |
Which repair method suits a home in Gwent?
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 happens when we carry out subsidence repairs in Gwent?
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.
Find the cause
An independent chartered structural engineer inspects the house and, where needed, arranges a drain survey, trial pits or soil tests. We can arrange the engineer. The aim is to know what is moving, and why, before money goes on repairs.
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.
Signs you may need subsidence repairs
- Wallpaper rippling or tearing where the wall meets the ceiling
- Doors and windows that start to stick or no longer close
- Diagonal cracks wider at the top, running from window or door corners
- Cracks that open in summer and partly close again in winter
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.
Towns in Gwent we cover for subsidence repairs
Subsidence repairs in Gwent: questions and answers
Is the ground in Gwent prone to subsidence?
The valleys of Blaenau Gwent, Torfaen and Islwyn lie on the South Wales coalfield with extensive historic workings and spoil tips, while Newport and Monmouthshire have Mercia Mudstone, alluvium and Old Red Sandstone. Historic coal workings are recorded beneath parts of Gwent, 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 Gwent?
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.
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.
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.
Should I cut down the tree near my house?
Not without advice, because felling a mature tree on clay can make things worse. As the roots stop drawing water, the clay swells and can lift the foundations, which is called heave. Pruning or staged removal may be advised instead. Check whether the tree is protected.