End-to-end refurbishment of London's mansion-block flats, period conversions, lateral apartments and contemporary penthouses. We manage Licence to Alter, Building Regulations Part E acoustic compliance, freeholder liaison, managing-agent protocols and full design-and-build under a single fixed-price contract — from the porter's desk to the polished plaster.
A flat refurbishment is fundamentally different from a house refurbishment, and most contractors have never internalised that difference. You are not just renovating your own four walls — you are working inside a multi-occupied building, governed by a lease, owned by a freeholder, managed by a third party, regulated by Building Regulations Part E acoustic standards, and overlooked by neighbours who will hear every drill, watch every delivery and remember every inconvenience.
The technical work is exacting. Acoustic specifications must satisfy Part E (45 dB DnT,w airborne, 62 dB L'nT,w impact for separating floors) and frequently a more demanding freeholder schedule on top. Wet rooms must be tanked to a standard that survives a leak claim from the flat below — a single failed shower membrane can produce a £40,000 dilapidations claim. Mansion-block freeholders demand specific contractor warranties, named insurance certificates and acoustic-test reports before a single radiator is unbolted.
The procedural work is equally demanding. Most leasehold flats require a Licence to Alter (LTA) from the freeholder or managing agent — a formal legal consent typically taking 6–14 weeks to negotiate, requiring drawings, schedules of works, contractor warranties, surveyor undertakings, lease covenant analysis and (often) a deed of variation. We have completed more than 180 LTA-governed flat refurbishments across Eaton Square, Cadogan Square, Lowndes Square, Albany, the Boltons, Park Lane, Knightsbridge, St John's Wood, Hampstead and Marylebone. Our LTA approval rate is 100%.
The result of doing this properly is a flat that achieves a house-quality refurbishment within the constraints of leasehold occupation — without the legal claims, the angry neighbour letters, the porter complaints, the building manager interventions, or the freeholder forfeiture threats that ruin so many London flat projects. We have built our reputation in Mayfair, Belgravia, Kensington, Knightsbridge, Chelsea and St John's Wood on this discipline alone.
A 1900 mansion-block flat in Knightsbridge and a 2018 lateral apartment in St John's Wood are entirely different technical projects. Below are the six flat typologies that account for the majority of our work — each with its own constraints, opportunities and price-per-sqm calibration.
The defining London apartment building — Whitehall Court, Albert Hall Mansions, Stafford Mansions, Hyde Park Mansions, Hampstead's Frognal & Wedderburn typology. Solid 13½" brick, raised-panel oak doors, plaster cornicing, often with a 24-hour porter and a strict freeholder. Every refurbishment requires LTA, structured acoustic specification and timed deliveries through the service entrance.
Originally single-family Victorian or Italianate stucco houses (Belgravia, Notting Hill, Bayswater, Hampstead, Primrose Hill) converted into 2–6 self-contained flats during the 1960s–1980s. Defining challenge: original conversion-era acoustic detailing is invariably substandard, requiring full Part E upgrade. Period features (cornicing, fireplaces, sashes) must be retained.
The defining prime-London apartment of the last twenty years — two or three adjacent flats laterally combined to form a single residence on one floor, typically with 200–500 sqm, multi-aspect outlook and concierge services. Refurbishment requires extensive structural opening between former demising walls, full Part E acoustic re-engineering and extensive M&E redistribution.
The top-floor or top-two-floor apartment with private roof terrace, often with floor-to-ceiling glazing, double-height living spaces and external lift access. Defining challenges: weight loading on roof terraces (porcelain pavers on pedestals, planters), wind-loading on external joinery, and integrated automation (motorised blinds, smart-glass, climate zoning).
The lower-ground or raised-ground floor of a converted period house, typically with private patio, light-well or rear garden access. Refurbishment focus: damp-proofing (almost always required at this level), waterproofing of bathrooms below water-table where applicable, sympathetic light-bringing strategies (Crittall screens, light-wells, glass roof pavement-lights).
Recent purpose-built apartments (Battersea Power Station, Chelsea Barracks, One Hyde Park, Centre Point, Gasholders, Lillie Square). NHBC or Premier warranted. Refurbishment focus: working within developer warranty constraints, navigating BSRA fire-safety compliance, and upgrading developer-spec finishes to a personalised standard without invalidating cover.
A Licence to Alter is the single most misunderstood — and most frequently mishandled — part of any London flat refurbishment. Get it right and your project starts on programme. Get it wrong and you face a 4–12 week delay, lease forfeiture risk and freeholder cost recovery. Here is exactly how we manage it.
Our chartered surveyor reads your lease, identifies alteration covenants, freeholder consent triggers, structural restrictions and any existing licences. Output: written lease summary.
Week 1Drawings (existing & proposed), structural calculations, schedule of works, Part E acoustic specification, contractor PI/PL insurance certificates and method statements compiled.
Weeks 2–3Application submitted to managing agent or freeholder direct. Standard fee (typically £750–£3,500) paid on your behalf and reimbursed on completion. Surveyor's appointment confirmed.
Week 4Freeholder's surveyor reviews and raises queries — usually around acoustic detailing, structural impact and warranty wording. We respond inside 5 working days. Mutual undertaking drafted.
Weeks 5–9Licence to Alter executed under hand or deed (depending on lease wording), signed by both parties, conditions noted. We provide the certified copy to your solicitor for safekeeping.
Weeks 10–14Critical fact most contractors don't tell you: we begin LTA preparation at design Stage 2 — running it in parallel with technical design and Building Control submission. By the time your contract is ready to sign, the LTA is engrossed and you are not waiting another 12 weeks to start on site. Most freeholders are not the obstacle most clients believe. Bad documentation is.
Twelve disciplines, all delivered in-house under a single fixed-price contract. Each line item below is contractually scoped, technically specified and warranted.
Lease audit, application pack preparation, drawings to freeholder's specification, structural calculations, acoustic spec, contractor warranties, surveyor negotiation and engrossment of the executed licence — all managed by our in-house RICS chartered surveyor and architect.
Full acoustic specification to Building Regulations Part E (45 dB DnT,w airborne, 62 dB L'nT,w impact). Resilient bar ceiling systems, dense rock wool quilt, acoustic-rated floor floating systems (Maxiboard, Cellecta YELOfon), pre- and post-works acoustic testing by ANC-accredited consultant.
BAL WP1, Schlüter-KERDI or Mapei Mapegum WPS waterproof tanking applied to floor and walls of every wet zone. Pre-tile flood test, certificated installation. 25-year insurance-backed leak warranty — single most important investment in any flat refurbishment.
NICEIC-certified rewire to BS 7671 18th Edition (Amendment 2) — full RCBO board, AFDDs, Cat6a structured cabling, Wi-Fi 6, smart-home pre-wire (Lutron, Crestron). Coordination with building riser, freeholder notification of consumer-unit upgrade, EICR sign-off.
Complete replumb in copper or Hep2O, hot water from Megaflo unvented or building-supplied riser, individual plate heat exchanger where applicable. New radiators or underfloor heating where slab depth permits. Full coordination with building risers and waste stacks. Gas Safe certified.
In-house kitchen design with handmade cabinetry, premium stone (book-matched marble, dolomite, quartzite) and full integrated appliance packages — Miele, Sub-Zero, Wolf, Gaggenau. Lift-access scheduling and protective wrapping for delivery into mansion-block service lifts.
Wall-hung sanitaryware (Duravit, Catalano, Villeroy & Boch), brassware (Vola, Dornbracht, Lefroy Brooks), frameless shower screens, freestanding baths, electric or low-profile hydronic underfloor heating. Steam and rainshower integration where ceiling void and acoustic build-up allow.
Floor-to-ceiling fitted wardrobes, dressing rooms, library shelving, kitchen cabinetry, alcove storage, internal doors, panelled walls and skirting/architrave to period or contemporary detail. Acoustic-rated where forming part of separating wall build-up.
Original sash windows, cornicing, ceiling roses, fireplaces, dado rails, parquet flooring and panelled doors retained, repaired or faithfully reproduced where lost. Heritage-trained joiners and plasterers on long-term framework.
Five-coat decoration (primer, two undercoats, two finish coats) in Farrow & Ball, Edward Bulmer, Paint & Paper Library or Little Greene. Specialist finishes: Venetian polished plaster, hand-painted joinery, lime wash, fabric-lined walls, hand-printed wallpaper hanging.
Direct relationship with porters, building managers, freeholders' surveyors. Agreed delivery hours, lift bookings, dust suppression, daily public-area cleaning, neighbour communication, parking suspensions and skip permits — all managed without your involvement.
Two-stage snagging — internal pre-handover walk by project manager and QS, then joint walk with you. Defects fixed before completion. 12-month JCT defects-rectification period, 10-year insurance-backed workmanship warranty, 25-year tanking warranty on wet rooms.
Part E governs sound insulation between dwellings — and it is the single most common reason a flat refurbishment becomes a legal claim. We design every project to exceed Part E minimums and the more demanding spec your freeholder will impose.
Pre- and post-works testing by ANC-accredited consultant included on premium projects.
There is no single price for a London flat refurbishment — the answer depends entirely on the specification you choose. Here is exactly how the four tiers we offer differ, line by line.
For a representative high-end (Considered tier) refurbishment of a 110 sqm two-bedroom mansion-block flat at £1,000/sqm — total contract £110,000. Here is the honest breakdown.
Successful mansion-block refurbishment is half technical and half procedural. Below is the standing protocol we apply on every project — refined across two decades inside Knightsbridge, Belgravia, Mayfair and Hampstead's most demanding addresses.
Letter delivered to every flat in the building 2 weeks before works commence — explaining scope, programme, daily working hours, contact details for our project manager, and apology for unavoidable disturbance. Builds neighbour goodwill before drilling starts.
Standard 0800–1700 Monday–Friday, no Saturday, no Sunday, no Bank Holiday. Noisy works (drilling, breaking, hammering) restricted to 0930–1230 and 1430–1630 to respect neighbour calls and naps. Quiet trades (decorating, second-fix) outside these windows.
Pre-booked weekly slots through the porter for material deliveries. Service lift wrapped with hardboard, paper and corner protection before any trade enters. Daily inspection by site manager. Damage rectification at our cost (rare, but in our policy).
Lobby carpet (or marble) covered with Correx, taped at edges. Hallway runners laid along entire route to your front door. Daily vacuum and clean of all areas affected by traffic. Lobby porter signs off cleanliness at end of every working day.
No skip on pavement. Materials bagged and removed daily through service exit by van — typically 10am and 3pm collections. Communal bins not used. Weekly cleaning of service-area stairwell where contractor traffic concentrates.
Floor-to-ceiling polythene zip-screen across your front door before any breaking work commences. HEPA-filtered vacuum extraction at point of dust generation. Daily wet-wiping of corridor outside front door. Air-quality monitoring on heritage projects.
Maximum two operatives in the lift at any time — no exceptions. Dust-free clothing, clean overshoe boot covers donned in the service lobby before entry to the building. No food or drink consumption in lifts or communal areas.
The porter is your first point of contact for issues during works. We give the porter our project manager's mobile and a sealed envelope with £150 cash for inconvenience — a Belgravia tradition that pays back tenfold in goodwill across an 18-week build.
Pre-completion acoustic test by ANC consultant. Full reinstatement of any communal area affected. Joint walk with porter and (where required) freeholder's surveyor before keys handed back. Practical Completion certificate copied to managing agent.
A representative programme for a 110 sqm two-bedroom Edwardian mansion-block flat at Considered specification, including LTA approval already in place. Yours will differ — but this is what a properly run flat refurbishment looks like in real time.
A non-exhaustive list of London managing agents and freeholders we have completed Licence-to-Alter projects with — confidentiality precludes naming clients, but you may verify our protocols through any of these organisations on request.
There are perhaps ten London design-and-build practices capable of delivering at this standard inside leasehold mansion blocks. Here is what makes us one of them.
180+ Licence to Alter applications submitted, 180+ approved. We know what every major London freeholder will require — and we deliver it first time.
One JCT agreement covering LTA, design, statutory approval, structural, M&E, acoustic build-up and finishes. No surprise variations.
Insurance-backed wet-room tanking warranty — protects you against the leak-claim risk that derails every poorly-executed flat refurbishment.
ANC-accredited acoustic consultant tests the existing build before works and certifies the completed work meets Part E and freeholder spec.
Pre-booked lift slots, daily lobby cleaning, restricted noisy hours, sealed dust screens — we leave the building cleaner than we found it.
The RIBA Chartered architect who designed your project walks the site every week of the build. Decisions made in person, not via email.
PI and PL cover at £10M — the level required by major London freeholders before they will even open an LTA application.
Insurance-backed workmanship warranty. 12-month JCT defects, free 6-month service visit, and a direct line to our project manager for the lifetime of the build.
Book a no-obligation consultation at our Finchley Road design studio or in your flat. The first meeting is free, lasts 60–90 minutes, and concludes with an honest indication of LTA risk, programme, budget band and feasibility. No salespeople. No pressure.
Site visit · lease audit · LTA risk assessment · outline cost estimate · programme indication. No obligation. Saturday appointments available.
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