Gwent · Wales
Structural crack repairs in Gwent
Across Gwent, requests for structural crack repairs usually begin with a crack someone has noticed getting wider. Clay soils are found in parts of Gwent. A repair only lasts if the reason for the movement has stopped.
Guide price from£75per metre of crack inc VAT

- Area
- Gwent
- Pricing region
- Wales
- Ground
- Clay in parts
- Towns listed
- 11
What should you know about the ground under Gwent?
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. Typical buildings in Gwent: Valley terraces on steep hillsides, Victorian houses in Newport and Abergavenny, and post-war estates.
Is it time for structural crack repairs? Common signs
- Daylight or a draught coming through a crack in an outside wall
- A crack noticeably wider at the top than the bottom, or the reverse
- Diagonal cracks running from the corners of windows and doors
- Cracks that reappear in the same place after filling and painting
What should you budget for structural crack repairs in Gwent?
For Gwent we use Wales rates. Treat the table as a budget guide, inc VAT; the price you pay is the one on your written quote.
| Item | Guide price | Per |
|---|---|---|
| Crack stitching with helical bars | £75 – £165 | per metre of crack |
| Single crack, outside only (up to about 2 m)est. | £370 – £830 | per crack |
| Internal making good and redecoration of the crack lineest. | £140 – £460 | per room |
Repair options we may recommend
Rebuilding a cracked section
Where bricks have split or the wall has moved out of line, the damaged area is taken down and rebuilt, bonded into sound masonry on either side. Reclaimed or matched bricks keep the repair discreet, with temporary support used where needed.
Best for: Badly displaced or broken brickwork
Filling and repointing
For hairline and narrow cracks that have stopped moving, the crack line is raked out and repointed in mortar matched to the original for strength, colour and texture. Inside, plaster cracks are cut out, filled with a flexible filler and redecorated.
Best for: Cracks up to about 5 mm that are no longer moving
Crack stitching with helical bars
Stainless steel helical bars are grouted into slots cut along the bed joints, bridging the crack so the masonry works as one piece again. It is the standard repair for wider stepped and vertical cracks once whatever caused them has stopped.
Best for: Stable cracks wider than about 5 mm, or ones that keep reopening
What to expect when we carry out structural crack repairs
Send photos
Photograph the crack from a distance and close up, with a coin or tape measure for scale. From these we say whether it looks cosmetic, needs a visit or calls for an engineer.
Survey and record
On site we measure the width along the crack, note its pattern and check nearby drains, trees and openings. If the cause is unclear, gauges can be fixed across it and read over several months.
Deal with the cause
Leaking drains, failed ties, a sagging lintel or ground movement are put right first, sometimes through an insurance claim. Repairing a crack before its cause is fixed usually means paying for the same job twice.
Do you need approval for structural crack repairs in Wales?
In Wales, small like-for-like repairs do not usually need approval, but work that alters or strengthens the structure needs building control under the Welsh Building Regulations, and the Party Wall etc. Act 1996 can apply to shared walls.
Structural crack repairs near you in Gwent
Your structural crack repairs questions
Does the ground around Newport cause cracking?
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 structural crack repairs cost in Gwent?
On Wales rates, structural crack repairs starts from about £75 per metre of crack, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Are horizontal cracks in a wall serious?
Horizontal cracks are often more serious than vertical ones, because they suggest the wall is being pushed or lifted. Cracks repeating every few courses point to rusting wall ties, while one long crack with a bulge may mean lost restraint.
What causes vertical cracks in walls?
Vertical cracks are most often caused by thermal or moisture movement in long walls, or by the joint between old and newer work. An even-width vertical crack is usually cosmetic. One clearly wider at the top or bottom can indicate foundation movement at one end.
When is a crack in a wall structural?
A crack is more likely to be structural when it is wider than about 5 mm, tapers, passes through the whole wall or keeps growing. BRE Digest 251 treats damage up to about 5 mm as aesthetic and over 25 mm as a stability concern. Width is a guide, not a diagnosis.