Underpinning in Cardiff
Surveys, design, and installation across Cardiff and surrounding towns.
- UK-wide coverage and local knowledge
- 20 year remedial warranty
- Diagnostics to remedial work
Our Cardiff team handles foundation repair across the wider Cardiff area. We regularly work in Barry, Penarth, Pontypridd, Caerphilly and Bridgend, on Victorian terraces, semi-detached houses, modern builds, and commercial properties.
Local coverage
Every job starts with a free site survey. A chartered structural engineer signs off the design before any work begins, and the installation is backed by a 10-year workmanship guarantee.
Ground conditions in Cardiff
moderate prevalenceCoal Measures, Mercia Mudstone, and made-up ground from the South Wales coalfield.
Former mining and tipped ground are the main causes of movement.
- Mercia Mudstone bedrock
- Tidal alluvium near the bay
- Made-up ground from historic dock infill
Methods we use locally
The right method depends on soil conditions, depth of failure, and access on site. The engineer's design decides, these are the options on the table for Cardiff properties.
| Method | Time on site | Best for in Cardiff |
|---|---|---|
|
Beam and base
Reinforced concrete beams that spread the load. |
2 to 6 weeks | Variable ground, bay windows, redistributing loads. Common on bay windows and settled extensions through Pontypridd and Caerphilly where loads need redistributing along a single elevation. |
|
Foam injection
Lightweight stabilisation that works to depth. |
1 day for most jobs | Slab re-levelling, void fill, conservatory bases. Useful for re-levelling slabs and floors in Caerphilly and Bridgend, where access for excavation is tight and disruption must be kept low. |
|
Mass concrete
The traditional method, done properly. |
2 to 6 weeks per elevation | Shallow failures on traditional ground, insurance claims. Well-suited to traditional brick properties across Cardiff, Barry and Penarth where shallow bays can reach competent ground by hand. |
|
Mini piled
When the good ground is a long way down. |
1 to 3 weeks on site | Deep bearing layers, made-up ground, restricted access. The usual answer for deep clay or made-up ground around Cardiff and Bridgend, and for rear-only access through the property. |
|
Resin injection
Targeted ground improvement, no excavation. |
1 day for most jobs | Granular soils, intact foundations, voids and density loss. Quick non-disruptive fix for shallow void filling and ground stabilisation across Cardiff, suited to lighter loads in Barry and Pontypridd. |
|
Screw pile
Helical piles, no concrete cure time. |
2 to 5 days | Lighter loads, time-critical jobs, conservatories. Low-vibration option for terraces close to neighbours in Penarth and Barry, with quick installation and minimal spoil. |
Areas we cover near Cardiff
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Common questions
Need an opinion on a Cardiff property?
A surveyor will be in touch within 48 hours.