07450 310772sales@uhmbasements.co.uk FMB  ·  Delta Registered  ·  £10M Insured  ·  25-Year Warranty About Services Areas Our Work Reviews Contact 07450 310772Book a site visit Home/ServicesOur services # London basement services, delivered end-to-end. A single directly-employed team covering every stage of a London basement: from planning and excavation to waterproofing, fit-out and warranty. 150+ basements delivered, 25-year warranty, £10M insurance. - ## Basement Excavation London Full sub-house excavation and structural forming: party-wall management, temporary works and soil disposal handled in-house. Learn more → - ## Basement Conversion London Turn sub-floor space into a fully habitable lower ground floor: kitchen-diners, guest suites, cinemas and gyms, delivered end-to-end. Learn more → - ## Basement Waterproofing & Tanking London Delta Registered Type A + Type C designs to BS 8102:2022 with 25-year warranty, installed by our own operatives. Learn more → - ## Basement Underpinning London Sequenced hit-and-miss underpinning designed and site-managed by NVQ Level 6 directors, 150+ terraces underpinned across London. Learn more → - ## Cellar Conversion London Lower headroom cellars converted into media rooms, wine stores and utility spaces: tanked, ventilated (MVHR) and lit to habitable standard. Learn more → - ## Basement Damp Proofing London Targeted damp diagnosis and remediation for period London properties: rising damp, salt contamination and condensation resolved. Learn more → - ## Sump & Pump Systems / Structural Waterproofing Twin-pump sump systems, battery back-up and combined Type A + C schemes for basements below the water table. Learn more → - ## Basement Extension London Rear and side basement extensions with structural glazing, light wells and re-landscaped gardens, planning through practical completion. Learn more → - ## Light Well Installation London Front and rear light wells with structural retaining walls, glazed covers and heritage-grade railings, bringing daylight to lower ground floors. Learn more → Book your free site visit ## Not sure which service you need? We'll tell you. A director attends every free site visit in person. If the project isn't right for us, we'll say so. If it is, you'll leave with a written scope, a fixed price and a delivery programme. - Free site visit - Written quote - 25-year warranty - £10M insuranceRequest your free quote 07450 310772 Underhouse Management Ltd, London's structural basement specialists. A directly-employed team of 25, delivering meticulous below-ground work across the capital's finest addresses. Established 2009. FMB·Delta Registered·Considerate Constructors ### Services - Basement Excavation - Basement Conversion - Waterproofing & Tanking - Underpinning - Cellar Conversion - Basement Extension ### Areas Served - London - Wandsworth - Clapham - Wimbledon - Putney - Balham - Chelsea - Kensington - Richmond upon Thames ### Contact - 07450 310772 - sales@uhmbasements.co.uk - Unit C220A, Trident Business Centre,89 Bickersteth Rd, London SW17 9SHBook a site visit © 2026 Underhouse Management Ltd (t/a UHM Basements). Company No. 06968521. Privacy Policy·Terms & Conditions·Cookie Policy·25-year warranty · £10M insurance Call nowBook a site visit