Basement specialistsin Chelsea ,SW3, SW10 & the Royal Borough.
Basement excavations, conversions and waterproofing across Chelsea: Chelsea Green, King's Road, Cheyne Walk, Sloane Square, World's End and the Boltons.
Our own 25-strong team · Free site visit and quote · 25-year warranty.
Chelsea basements are heritage-first, engineering-second.
Chelsea basements are unlike anything further south. Georgian and Victorian stucco-fronted townhouses, listed frontages, conservation area controls across almost the entire postcode, Party Wall Awards on both flanks and often across the rear, tight mews access and RBKC's specific basement subterranean development policy, heritage constraints define the project before engineering does. UHM has delivered more than a dozen basements inside SW3 and SW10 in the last decade.
All SW3 and SW10 postcodes and neighbouring SW1 and SW7. Deepest coverage in Chelsea Green, King's Road, Cheyne Walk, Sloane Square edges, the Boltons and World's End.
Call or email and a director will get back to you to arrange a free site visit at a time that suits you.
Georgian and Victorian townhouses, stucco-fronted terraces, mews houses, listed buildings, converted mansion flats, and Grade II heritage stock across the RBKC.
Full basement excavations under listed Georgian houses, cellar conversions to habitable rooms, wine-cellar and cinema fit-outs, heritage-appropriate waterproofing retrofits, and light wells engineered inside conservation-area consent constraints.
Every basement discipline, under one roof.
Every UHM basement discipline is delivered across Chelsea, adapted for heritage constraints. Each service link below explains the technical detail and warranty position, but on Chelsea projects, the consent programme often exceeds the build programme.
Basement Excavation
New basements dug beneath Chelsea's Georgian and Victorian townhouses, heritage-appropriate sequencing on listed frontages.
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Basement Conversion
Fully habitable Chelsea lower-ground floors, wine cellars, cinemas, spas, matched ceiling heights, listed-interior sympathetic.
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Waterproofing & Tanking
BS 8102 Type C cavity drainage across Chelsea, Delta Registered, 25-year insurance-backed warranty.
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Underpinning
Structural underpinning across Chelsea's Georgian and Victorian foundations, Temporary Works Coordinator on every job.
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Cellar Conversion
Convert existing Chelsea cellars: perfect for wine storage, cinemas and studies inside listed frontages.
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Damp Proofing
Diagnostic damp surveys across Chelsea, targeted damp-proofing sympathetic to listed interior fabric.
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Sump & Pump Systems
Twin-pump, alarmed sump systems installed and commissioned across Chelsea, the mechanical backbone of a dry basement.
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Basement Extension
Downward extensions in Chelsea where outward extension is prohibited, full RBKC planning and Party Wall service.
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Light Well Installation
Engineered light wells for listed Chelsea plans, consent-aware, heritage-appropriate detailing.
Learn moreWhy Chelsea homeowners choose UHM.
Chelsea basement projects fail more often on consent and heritage than on engineering. A team that handles heritage sequencing in-house is the single biggest predictor of a project delivered on time and without conservation-officer disputes.
One accountable team, start to finish
Recent and live projects across Chelsea Green, King's Road side streets, Cheyne Walk and the Boltons. Every one delivered by our own 25-strong directly-employed team.
RBKC-consent fluent
We handle RBKC Building Control, conservation area consent, listed building consent and Party Wall Awards routinely. Their subterranean development policy is complex | we plan for it inside the project programme, not after tender.
Heritage-appropriate methods
Underpinning sequences for Grade II stucco frontages, careful façade-load management, and reversible internal detailing on listed interiors | all handled in-house by our own team.
The specific problems Chelsea basements face.
Chelsea basements fail predictably: not from ground or water but from heritage, consent, party wall density and RBKC-specific planning policy. Every UHM design programme starts by engineering those risks out.
Listed façades & stucco fronts
Chelsea's Georgian and Victorian townhouses often have listed façades and stucco fronts with settlement-cracked lime render. Underpinning must be sequenced not to lift or drop stucco panels | Temporary Works Coordinator on every heritage job.
Conservation area & Article 4 controls
Almost the entire SW3 postcode is inside conservation areas with Article 4 directions removing permitted development rights. Light wells, external stairs, planting removal | all need consent and lead time.
RBKC subterranean development policy
The Royal Borough operates its own basement policy with specific rules on depth, projection, garden loss and construction management. UHM plans against that policy pre-tender | never trying to retrofit compliance later.
Party walls on three flanks
Chelsea townhouses commonly share flanks and often rears with neighbours. Notices, awards and adjoining-owner surveyor liaison are standard | we manage them all inside the scope.
Structured stages, no shortcuts.
Every UHM project, whether in Chelsea or elsewhere in London, runs through the same disciplined sequence. You'll always know what's happening next, who's doing it and when it completes.
- 01
Free Chelsea site visit
Director-led survey of your SW3 or SW10 property | measured, photographed and listed-building noted.
- 02
Fixed written quote
Structural strategy, BS 8102 waterproofing spec and RBKC conservation notes | priced in writing.
- 03
Consents & Party Wall
RBKC Building Control, conservation area consent, listed building consent, Party Wall Awards | managed end to end.
- 04
Build on-site
Directly-employed team on your Chelsea site. Heritage-appropriate methods, protected façades, tight logistics.
- 05
Handover & warranty
Sign-off, twin-pump commissioning, 25-year structural and waterproofing warranties.
Do you serve Chelsea?
Yes. Chelsea SW3 and SW10 are core UHM areas with completed basement projects across Chelsea Green, King's Road, Cheyne Walk and the Boltons.
How fast can you reach Chelsea?
Get in touch by phone or email and we will arrange a free, director-led site visit at a time that suits you.
How much does a Chelsea basement cost?
Chelsea basements are typically higher-specification and more consent-intensive than the wider South London average, but every quote is written after a real site visit, with heritage constraints priced in transparently.
Do you handle RBKC Building Control, conservation area consent and listed building consent?
Yes. UHM manages Building Control with the Royal Borough of Kensington and Chelsea, plus conservation area consent, listed building consent where required, and Party Wall Awards, all inside the standard scope.
Can you work on listed buildings in Chelsea?
Yes, subject to listed building consent. Listed projects need slower, more careful sequencing and more consent time, we plan for it in the programme, and we won't quote a heritage project until we've seen it.
How does RBKC's basement policy affect what we can build?
The Royal Borough restricts depth, garden loss and specific construction management practices. It does not prevent basements, but it constrains them, UHM will explain what your specific address can and cannot accommodate at the free site visit.
Serving South & West London
Book your Chelsea site visit.
Free, director-led, heritage-aware. On listed and conservation-area Chelsea properties we'll walk the frontage, note constraints, and price the work realistically in writing.
- Free site visit
- Free written quote
- 25-year warranty
- £10M insurance
- Directly-employed team