UNDERPINNING SPECIALISTS — London
Underpinning Contractor London
Underpinning contractor covering all London boroughs. We carry out foundation stabilisation and deepening across the capital, from Victorian terraces in south London to Georgian townhouses in the west, working to structural engineer specifications throughout.
Ground Conditions in London
London's geology varies significantly across the capital — from London Clay in the west and north, to Thames river terrace gravels in riverside areas, chalk in the south, and alluvial deposits in the east. Each soil type presents different challenges for foundation stability and underpinning design.
We work across all London boroughs and are familiar with the planning and building control requirements of each. We work with structural engineers and planning consultants experienced in each area to ensure all works are properly consented.
Property Types We Underpin
London has an enormous stock of Victorian and Edwardian terraced houses, Georgian townhouses and inter-war semis, the vast majority of which have shallow strip foundations. Underpinning is required for basement conversions, to address subsidence and to stabilise foundations affected by adjacent construction.
- Foundation settlement or subsidence
- Basement conversion requiring deeper foundations
- Adjacent construction affecting existing foundations
- Change of use increasing structural loads
- Damaged or inadequate original foundations
Underpinning Methods We Use in London
London's varied geology means method selection is critical. We carry out ground investigation before specifying the underpinning approach, ensuring the chosen method suits both the soil profile and the structural loads involved.
Mass Concrete Underpinning
The traditional pit method — sections of existing foundation are excavated and replaced with mass concrete in a controlled sequence to maintain structural stability throughout.
Beam and Base Underpinning
A reinforced concrete beam transfers load to new concrete bases, ideal where ground conditions require load spread across a wider area.
Mini-Pile Underpinning
Steel piles driven or bored to load-bearing strata below problematic soils. Suited to restricted access, deep foundations and areas with significant ground movement history.
Related Services in London
Underpinning FAQs — London
How long does underpinning take?
Most domestic underpinning projects take between 2 and 6 weeks depending on the depth, method and number of bays required. We provide a detailed programme before work begins.
Do I need planning permission for underpinning?
Underpinning to repair or stabilise existing foundations is generally permitted development. If the underpinning forms part of a basement conversion or extension, planning permission may be required. We advise on this during the survey.
Will underpinning affect my home insurance?
You must notify your insurer before underpinning work begins. Most insurers will continue cover during and after the works. We provide full documentation including structural engineer sign-off to support your insurance records.
How much does underpinning cost?
Costs vary with depth, method and site access. Mass concrete underpinning typically starts from £1,500–£2,500 per bay. We provide a fixed-price quote after a free structural survey.
Is underpinning covered by a guarantee?
Yes. All our underpinning work is backed by our 25-year structural guarantee and £10m public liability insurance. We also provide a structural engineer completion certificate.
Need an Underpinning Contractor in London?
We carry out structural surveys, produce method statements and manage the full underpinning programme from start to finish. Call us or request a quote online.