The short answer
Underpinning a house in the UK typically costs around £6,000–£21,000+, with a standard three-bedroom semi-detached commonly landing in the £10,000–£15,000 region for traditional mass-concrete work. Complex, deep or London projects can run higher, sometimes to £25,000 or more. The total is driven by how much of the foundation is affected, the method used, the depth of digging, and the professional fees — a structural engineer's assessment and ongoing monitoring are usually part of the cost, not extras to forget. Alternative methods such as resin injection or mini-piling sit at different price points, so the right figure for your home only comes from a measured, engineer-led assessment.
Underpinning is priced on the work involved, not a flat fee — the affected length, the depth, the method and the engineer's fees all feed into it. The figures below are typical UK ranges for guidance, not quotations.
Typical UK costs
- Whole-house (typical)£6,000–£21,000+
- Semi-detached (common)~£10,000–£15,000
- Complex / deep / London£25,000+
- Structural engineerusually included in scope
- Methodmass concrete, resin or mini-piling
What drives the price
- Affected length & area: you largely pay for the run of wall and the area of foundation that needs work — a localised corner costs far less than a whole elevation.
- Method: traditional mass concrete, beam-and-base, mini-piling and resin injection sit at different price points and suit different ground conditions.
- Depth & access: deeper foundations, awkward access and obstructions such as drains or services all add time and cost.
- Professional fees: a structural engineer's assessment, design and monitoring are normally part of the job, alongside building control involvement.
| Item | Typical figure | Notes |
|---|---|---|
| Whole-house underpinning | £6,000–£21,000+ | varies widely by scope |
| Standard semi (mass concrete) | ~£10,000–£15,000 | common reference point |
| Complex / deep / London | £25,000+ | premium rates & depth |
| Resin injection (per m²) | ~£1,200 / m² | less disruptive method |
Indicative UK figures for guidance. Sources: Checkatrade and MyJobQuote underpinning cost guides.
Why the range is so wide
Underpinning costs vary more than most building jobs because so much depends on the ground and the cause. Two houses on the same street can need very different work — one a short, shallow repair to a single corner, the other a deeper job across a whole elevation. The method, the depth, the soil and the professional fees all move the figure, which is why a single point price is misleading. A structural engineer's report turns the range into an accurate number for your property.
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We'll match you with a vetted structural/underpinning contractor who works from a structural engineer's findings and quotes on a clear specification — method, length, depth and fees all set out.
Frequently asked questions
How much does it cost to underpin a house?
Typically around £6,000–£21,000+ in the UK, with a standard semi-detached commonly £10,000–£15,000 for mass-concrete work. Complex, deep or London jobs can reach £25,000 or more, depending on the method, depth and affected length.
Does the cost include the structural engineer?
It usually should. A structural engineer's assessment, design and monitoring are normally part of an underpinning job, so check whether a quote includes those fees, building control and any monitoring period.
Why is the underpinning cost range so wide?
Because it depends on the cause, the ground, the method and how much of the foundation is affected. A localised corner repair is far cheaper than a deep job across a whole elevation. An engineer's report gives the accurate figure for your home.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on your specific property. They are guidance, not a quotation.