Stevenage · Hertfordshire
Underpinning in Stevenage
Most underpinning in Stevenage, as elsewhere, is partial, strengthening one corner or a single wall rather than the whole house. The engineer plans how the new foundation meets the old so that the junction does not become the next place to crack.
Guide price from£1,050per metre of wall inc VAT

- Postcodes
- SG1, SG2
- Population
- about 92,000
- Area
- Hertfordshire
- Pricing region
- East of England
Why does the ground in Hertfordshire matter for underpinning?
Stevenage, Hertfordshire: about 92,000 residents across postcode districts SG1, SG2. Neighbouring towns we cover: Hitchin (5 miles), Letchworth Garden City (5 miles) and Welwyn Garden City (7 miles).
Shrinkable clay is widespread in Hertfordshire. Ground movement here is more often linked to soils, drains and trees than to mining. Housing stock in Hertfordshire: Garden-city houses in Letchworth and Welwyn, 1930s semis, Victorian terraces and post-war new-town estates.
Methods for underpinning
Mass concrete underpinning
The traditional method. Short sections under the wall are dug out in a set sequence, usually about a metre at a time, and filled with concrete before the next section is opened. It suits moderate depths and good access, and it needs little specialist plant.
Best for: Shallow failures on firm ground found at moderate depth
Beam-and-base underpinning
A reinforced concrete beam is cast beneath or alongside the existing footing and carries the wall onto mass concrete bases at intervals. It spreads load well across variable ground and can mean less digging than continuous underpinning along the whole wall.
Best for: Longer runs of wall or heavier loads over variable ground
From first photo to finished repair
Engineer’s investigation
An independent chartered structural engineer studies the monitoring results, trial pits and soil tests, then decides whether underpinning is needed and which method suits. We can arrange the engineer if you do not already have one.
Excavation and concrete
Work runs in the sequence the engineer sets so the wall is never left unsupported over a long length. Building control inspects the excavations before concrete goes in, and each section is dry-packed tight to the footing above.
Crack repairs and handover
Once the new foundation has cured, cracks are stitched and repointed, inside walls are made good, and paths or patios disturbed by the dig are reinstated. You receive the building control completion paperwork for your records.
Symptoms that point to underpinning
- Footings found to be very shallow during a trial pit
- A large tree nearby that cannot be removed or reduced
- Floors sloping noticeably towards one external wall
Guide prices for underpinning in Stevenage
The ranges below reflect typical East of England costs for underpinning, including VAT. Scaffold, access and making good can push a job to the top of the range.
| Item | Guide price | Per |
|---|---|---|
| Mass-concrete underpinning | £1,050 – £1,600 | per metre of wall |
| Beam-and-base underpinning | £1,600 – £2,600 | per metre of wall |
| Mini-piled underpinning | £2,100 – £3,700 | per metre of wall |
| Engineer's design and building control feesest. | £840 – £2,600 | per scheme |
Rules for underpinning in England
In England, underpinning and other work that alters or strengthens a wall or foundation is building work under the Building Regulations (Part A, structure), so building control approves and inspects it. Like-for-like repairs often are not, and we tell you which applies before a price is agreed. Work to a party wall, or excavation close to a neighbour’s foundations, can also need a notice under the Party Wall etc. Act 1996.
Frequently asked questions
How much should I budget for underpinning in Stevenage?
Guide prices for underpinning in Stevenage start from about £1,050 per metre of wall, including VAT, on East of England rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Can you survey a property in Stevenage?
We do. Stevenage and the surrounding area are covered, including nearby Hitchin and Letchworth Garden City. A free initial assessment from your photos is the first step.
Why do houses in Hertfordshire crack?
South Hertfordshire around Watford, Borehamwood and Potters Bar is London Clay, while the north and west are chalk with clay-with-flints and the east has boulder clay. The clay areas are prone to seasonal subsidence near trees. Only an investigation can say why a particular building has moved.
Which underpinning method is best?
The right method depends on how deep firm ground lies, the load on the wall and the access. Mass concrete suits moderate depths, beam-and-base spreads heavier loads, and mini-piles reach deep soft ground or work through tight access. The engineer chooses the method from the site investigation.
Will underpinning affect selling my house?
It needs explaining to buyers, but a properly documented scheme is far better than unresolved movement. Keep the engineer’s design, the building control completion certificate and any insurance paperwork. Lenders and surveyors will usually ask for these before agreeing a sale.
Related work in Stevenage
- Bay window subsidence repairs
- Floor joist repairs
- Structural surveys and crack monitoring
- Structural crack repairs
- Chimney stack repairs
Underpinning near Stevenage
For a no-obligation written quote on underpinning in Stevenage, send photos of the cracking and any engineer’s report you already hold.