Creating additional basement space beneath an existing property can require the foundations to be taken deeper. Underpinning provides a way to strengthen and extend foundation support as the proposed lower level takes shape. The work calls for careful sequencing, suitable construction methods and close attention to the building above.
WJB Groundworks carries out underpinning as part of its wider groundworks and construction services across Greater London. Since 2014, we have supported residential and commercial construction projects with practical site-based expertise.
Our team works on projects involving foundations, excavation, drainage and concrete construction, allowing related activities to be coordinated through one contractor. Planning a basement project? Contact WJB Groundworks to discuss your underpinning requirements.
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Consult with our specialists and book an on-site inspection at your convenience. Contact us at 02037541809, or email us at info@wjbgroundworks.com for a bespoke quote. Visit our portfolio and explore the projects we have conducted successfully.
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Existing properties present their own set of conditions. Foundation depth, masonry, soil, neighbouring structures and the intended basement level can all influence how the work is approached.
A suitable sequence helps maintain stability while new foundation support is introduced beneath the existing structure.
The wider construction plan matters too. Underpinning may need to connect with excavation, drainage, new slabs, retaining structures or other structural works.
Unlike many basement underpinning firms, our groundworks background allows these requirements to be considered as part of the same project rather than treated as isolated construction tasks.
Speak to our team today about the groundworks your basement project requires.
We provide underpinning and associated groundworks for London properties requiring additional foundation support or deeper below-ground construction. Our services include:
● Basement underpinning to support deeper excavation beneath existing properties.
● Foundation strengthening where existing foundations require additional structural support.
● Underpinning for basement conversions where creating additional below-ground space forms part of the project.
● Excavation works coordinated with the required underpinning sequence and wider groundworks.
● Concrete foundation construction for new or extended below-ground structures.
● Basement drainage to manage water as part of wider below-ground construction.
● Site preparation including excavation and groundwork before structural construction begins.
● Structural concrete works supporting basement slabs, walls and other project requirements.
● Integrated groundworks where underpinning needs to be combined with other construction services.
With excavation, foundations, drainage and concrete construction available from one team, we can help keep your basement project moving without unnecessary contractor handovers. Tell us what you're planning, and we'll help establish the right scope for your project.
When looking for basement underpinning firms, clients want more than a team that can carry out underpinning. They need construction experience around the foundation work itself. Here is why clients choose WJB Ground Works:
Our underpinning work is supported by wider experience in excavation, foundations, drainage and concrete construction.
WJB Groundworks has been delivering construction services across Greater London for more than a decade.
Related groundworks can be coordinated within the same project, reducing the need to manage multiple construction contractors.
We work with residential clients on projects involving existing properties, foundation alterations and below-ground construction.
Our team also supports commercial construction schemes where underpinning forms part of a broader development.
We operate across Greater London, with additional project coverage extending into Surrey, Essex and Luton.
Project managers, engineers and skilled tradespeople work together throughout the construction process.
Our award-winning safety team supports rigorous working practices across our construction sites.
Clients have a consistent team to communicate with as the work progresses through different construction stages.
Underpinning can sit alongside our other groundworks and structural capabilities when a project requires a broader scope.

STEP-01
We establish the site's requirements, review the proposed excavation and identify the groundworks needed to support the construction programme.
STEP-02
Underpinning proceeds in planned stages, providing additional support as the project moves towards the required basement depth.
STEP-03
Excavation continues alongside the wider construction programme, followed by slabs, walls, drainage and other required structural elements.
STEP-04
Completed works are reviewed, outstanding details addressed and the finished area prepared for the next phase of the development.
Consult with our specialists and book an on-site inspection at your convenience. Contact us at 02037541809, or email us at info@wjbgroundworks.com for a bespoke quote. Visit our portfolio and explore the projects we have conducted successfully.
Basement underpinning firms strengthen or extend support beneath existing foundations so a property can accommodate deeper excavation.
Underpinning may be required when the proposed basement level extends below the existing foundation level. The actual requirement depends on the property's construction, existing foundations, ground conditions and the structural approach selected for the project.
Yes. Underpinning can form part of a basement construction project beneath an existing property.
The timeline for basement underpinning typically ranges from 3 to 8 weeks for an average-sized residential project, though larger or more complex jobs can take 3 to 6 months.
Yes. As one of the best firms for basement underpinning, WJB Groundworks provides excavation alongside its wider groundworks services. Combining the two can help coordinate the sequence of foundation support, soil removal, and subsequent basement construction.
Yes. Drainage can form part of a broader basement or foundation project where required.
Many underpinning projects form part of larger developments, including commercial construction. WJB Groundworks provides groundworks and construction services for both residential and commercial projects.
There is no standard price because every property has different foundations, ground conditions, access requirements and construction needs. Contact us today for a no-obligation free quote.