South Glamorgan · Wales
Concrete repairs in South Glamorgan
Concrete repairs in South Glamorgan starts with the ground. South Glamorgan has a mix of ground, with clay in some places and firmer rock in others, and the buildings here are mostly Victorian terraces in Cardiff and Penarth, so the repair has to suit both.
Guide price from£80per m² inc VAT

- Area
- South Glamorgan
- Pricing region
- Wales
- Ground
- Clay in parts
- Towns listed
- 4
Why does the ground in South Glamorgan matter for concrete repairs?
Cardiff is built on Mercia Mudstone, river gravels and alluvium, and the Vale of Glamorgan on Lias limestone and clay. Soft alluvium near the rivers and docks can settle.
Ground movement here is more often linked to soils, drains and trees than to mining. Housing stock in South Glamorgan: Victorian terraces in Cardiff and Penarth, inter-war semis and post-war estates.
Signs you may need concrete repairs
- Hollow sound when the surface is tapped with a hammer
- Rust-coloured stains or streaks running down the concrete surface
- Chunks or flakes of concrete breaking away from edges and soffits
- Damp patches, white deposits or drips on a balcony or canopy underside
How much will concrete repairs cost in South Glamorgan?
These are guide prices for South Glamorgan, 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 |
|---|---|---|
| Concrete patch repair | £80 – £165 | per m² |
| Crack injection | £165 – £440 | per metre |
| Small jobs (minimum visit)est. | £415 – £830 | per visit |
Which repair method suits a home in South Glamorgan?
Crack injection
Cracks are sealed at the surface, then a low-viscosity resin is injected under pressure through ports until it fills the crack. A rigid resin bonds the two faces back together, while a flexible one seals live cracks against water. The choice depends on whether the crack is still moving.
Best for: Cracks letting water in, or splitting a slab or beam
Protective coatings and sealing
After repair, an anti-carbonation coating, a waterproof deck membrane on a balcony, or a penetrating sealer slows the return of moisture and carbon dioxide. Restoring drips, upstands and falls so water drains away is as important as the coating itself.
Best for: Extending the life of repaired balconies and canopies
Recasting or strengthening
Where steel has lost much of its section, or a lintel or canopy is too far gone to patch, the element is propped and rebuilt, replaced or strengthened to an engineer’s design. It is less common, but sometimes the more lasting option for small canopies and old precast lintels.
Best for: Badly corroded lintels, canopies and balcony edges
What happens when we carry out concrete repairs in South Glamorgan?
Photos and a description
Send photos of the damage close up and from a distance, plus the whole balcony, canopy or elevation. Tell us roughly how old the building is and whether anything has fallen, so we can judge whether to make it safe first.
Survey and tapping test
On site we tap the surface to find hollow areas, check the steel where it is exposed and note drainage. Where the extent is unclear, a cover meter, carbonation test or chloride test may be advised before repair.
Written quote
You receive a no-obligation written quote setting out the estimated area of patching, the length of crack injection, coatings and access. It becomes a fixed price in writing once the repair is specified, with any re-measure terms stated clearly.
Do you need approval for concrete 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.
Find concrete repairs in your South Glamorgan town
Concrete repairs in South Glamorgan: questions and answers
Why do houses in South Glamorgan crack?
Cardiff is built on Mercia Mudstone, river gravels and alluvium, and the Vale of Glamorgan on Lias limestone and clay. Soft alluvium near the rivers and docks can settle. Ground movement here is more often linked to soils, drains and trees than to mining. Only an investigation on site can say why a particular building has moved.
How much will concrete repairs cost in South Glamorgan?
On Wales rates, concrete repairs starts from about £80 per m², including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
What is carbonation in concrete?
Carbonation is the gradual reaction between carbon dioxide in the air and concrete, which lowers its alkalinity from the surface inward. Alkaline concrete protects the steel inside, so when carbonation reaches the bars, they can start to rust. A simple test on a freshly broken surface shows how deep it has gone.
Why does concrete crack and rust?
Concrete cracks as it shrinks, moves with temperature or carries more load than intended. Steel inside it rusts when carbonation or salts reach it and moisture gets in. The two feed each other: cracks let water in, and rusting steel expands and cracks the concrete further.
Can you repair a cracked concrete lintel?
Often, yes. Spalling and small cracks in a concrete lintel can be patch repaired and the steel treated. If the lintel is badly cracked, sagging or the bars have lost much of their section, replacement is usually better, and the opening is propped while it is done.