Kitchen Extension Builders in Kensington (W8, W14)
Professional kitchen extension builders in Kensington, West London.
Why Choose All Well for Kitchen Extensions in Kensington?
Kitchen extensions in Kensington are among the most design-sensitive projects we take on. The stucco-fronted townhouses and period terraces are architectural treasures, and any extension needs to be worthy of the original building. We work with conservation architects to design rear extensions that satisfy the Royal Borough's stringent requirements while creating the open-plan kitchens that modern families need. The specifications are high, the standards are exacting, and the results are worth it.
Every project comes with a fixed-price contract, single project manager, and full certification including Building Control sign-off.
Kitchen Extensions for Kensington Properties
Kensington is known for its victorian terraces, stucco-fronted townhouses, mansion flats, conservation areas. Our kitchen extensions services are tailored to these property types, ensuring results that complement the character of your home.
Postcodes we cover: W8, W14, SW5
Kitchen Extensions Tip for Kensington Homeowners
Almost every property in Kensington is within a conservation area, and many are Grade II or Grade II* listed. Listed Building Consent is required for both internal and external works on listed properties, and the process typically takes 8-12 weeks. The Royal Borough of Kensington and Chelsea has one of the most demanding planning departments in London — applications need to be comprehensive, well-designed, and accompanied by a heritage impact assessment. We manage this process end-to-end with our heritage consultant.
Three Kensington kitchen extension patterns
Three patterns cover most of what we build in W8, W14, and SW5. Mansion flat kitchen reconfiguration with internal load-bearing wall removal is the most common Kensington project. Most Kensington period mansion blocks (Iverna Gardens, Cornwall Gardens, Kensington Court, Lexham Gardens) can't extend physically, but the original layout — separate kitchen with butler's pantry off a formal reception — needs reconfiguring into open-plan living. We open the load-bearing wall between kitchen and reception with a 178x102 UB or 203x133 UB steel beam (depending on span), reconfigure the plumbing for a new island layout, and install a luxury kitchen at premium specification. Cost is £80,000-£200,000 depending on scope, scale of structural opening-up, and specification. Build time 12-18 weeks. Section 20 leaseholder consultation, freeholder Licence to Alter, and structural engineer calculations apply. Rear extension on a stucco-fronted townhouse is the second pattern, where consented and design-acceptable. Conservation-sympathetic design uses traditional materials (London stock brick or matching render, slate or natural-appearance roofing, Crittall-style steel-frame doors) and proportions that subordinate to the original building. Cost is £150,000-£350,000 reflecting heritage materials, conservation architect coordination, and luxury kitchen specification. Build time 22-30 weeks including planning timeline. Listed Building Consent applies for almost all listed Kensington properties. Basement kitchen extension under existing footprint is the third pattern, common where above-ground extension isn't permitted. RBKC permits single-storey basement excavation under existing footprint subject to Basement Impact Assessment. Cost is £200,000-£500,000 for tanking, structure, and luxury kitchen fit-out. Build time 28-44 weeks. Multi-storey basements are restricted in most streets.
RBKC planning, Listed Building Consent, and basement policy
Three Kensington-specific factors define every kitchen project — the Royal Borough has some of the most stringent planning policies in London. Listed Building Consent. Most Kensington period properties are Grade II or Grade II* listed. Listed Building Consent is required for virtually any change including internal layout alterations, removal or alteration of original features (cornicing, ceiling roses, fireplaces, panelled doors, decorative plasterwork), replacement of original windows or doors, render colour changes, and roof material changes. Application takes 12-16 weeks at RBKC, which has one of London's most demanding heritage teams. We work with conservation-specialist architects on every listed project and use heritage materials matched to the original — lime mortar, slate, timber, conservation-grade glass. Listed Kensington kitchen work typically costs 40-70% more than equivalent work on a non-listed property and takes longer. Basement policy and Basement Impact Assessment. RBKC introduced strict basement policy following neighbour complaints and structural concerns in streets with multiple basement conversions. Requirements now include a Basement Impact Assessment (covering hydrogeology, structural impact on neighbouring properties, and ground conditions), a Construction Traffic Management Plan, and a Construction Management Plan covering hours of work, vehicle movements, dust, and noise. Single-storey basements are typically permitted; multi-storey basements are restricted in most streets. Application costs and timelines are significantly higher than for above-ground extensions. Mansion-block Section 20 and Licence to Alter. Most Kensington mansion blocks operate under leasehold structures with Section 20 consultation requirements for major works under the Landlord and Tenant Act 1985. Internal kitchen reconfiguration with structural opening-up always requires Licence to Alter from the freeholder, with the freeholder's surveyor reviewing structural calculations before consent is granted. Application to the freeholder takes 6-16 weeks depending on the management company. We coordinate the application and licence as part of the project.
Project management on a Kensington kitchen project
A Kensington kitchen project involves 14-20 trades over 12-30 weeks: demolition, foundations and any basement excavation, drainage, structural steel, brick and block (heritage matching), roofing, glazing (often heritage timber sash plus Crittall steel doors), plastering (lime-based on listed properties), electrics (NICEIC to BS 7671 — concealed routing through 18-24 inch solid walls without damaging original plaster), plumbing, gas (Gas Safe), bespoke kitchen joinery (Bulthaup, Boffi, Smallbone, Roundhouse), natural stone (Calacatta or Statuario marble) or Dekton worktops, premium appliances (Wolf, Sub-Zero, Miele, Gaggenau), tiling, flooring, painting (heritage colours, hand-applied finishes on listed properties), plus heritage trades on listed projects. We assign one project manager from survey through handover with photo updates throughout the build. Fixed-price contracts cover labour, materials, structural engineer calculations (£1,500-£4,000 for the steel and foundation design pack including basement structural calculations where applicable), Building Control fees (£800-£1,500 at RBKC), FENSA glazing registration, party wall surveyor coordination, conservation architect coordination, heritage consultant fees, Listed Building Consent fees, planning fees, Section 20 leaseholder consultation, Licence to Alter coordination, Basement Impact Assessment where applicable, and Construction Management Plan where required. The price doesn't change unless the specification does. Building Control inspections happen at foundation, DPC, drainage, structural steel, insulation (Part L: U-value 0.18 W/m²K for new walls and roof), and completion. Heritage materials and standards apply on listed projects. Premium appliances include Wolf or Sub-Zero American refrigeration, Miele or Gaggenau ovens, Quooker boiling taps, and Calacatta or Statuario marble or Dekton worktops.
Kitchen Extensions in Kensington: What's Included
Kitchen Extensions Pricing in Kensington
£45,000 – £90,000
10–14 weeks | Fixed-price contracts | No hidden costs
What Our Customers Say
“All Well managed our project from start to finish. The fixed-price contract meant no surprises, and the result is stunning.”
Verified Customer
Kensington
“Professional team, clear communication throughout. They handled everything including Building Control sign-off.”
Verified Customer
Kensington
Frequently Asked Questions
- How much does a Kensington kitchen project cost?
- Mansion flat kitchen reconfiguration with internal load-bearing wall removal (the most common Kensington project) runs £80,000-£200,000 depending on scope, scale of structural opening-up, and specification. Rear extension on a stucco-fronted townhouse runs £150,000-£350,000 reflecting heritage materials and luxury kitchen specification. Basement kitchen extension under existing footprint runs £200,000-£500,000 including tanking, structure, and fit-out. Listed Building Consent on Grade II properties typically adds 40-70% to construction cost. Section 20 consultation and Licence to Alter on mansion flats add £2,500-£6,000 in coordination and structural calculations. Basement Impact Assessment adds £8,000-£20,000. Construction Management Plan adds £5,000-£15,000. Fixed-price contract before any work starts.
- What's involved in working on a listed Kensington property?
- Substantial planning preparation. Most Kensington period properties are Grade II or Grade II* listed, requiring Listed Building Consent for virtually any change including internal layout alterations, removal or alteration of original features (cornicing, ceiling roses, fireplaces, panelled doors, decorative plasterwork), replacement of original windows or doors, render colour, and roof material changes. Application takes 12-16 weeks at the Royal Borough of Kensington and Chelsea, which has one of London's most demanding heritage teams. We work with conservation-specialist architects on every listed project and use heritage materials matched to the original — lime mortar, slate, timber, conservation-grade glass. Listed Kensington work typically costs 40-70% more than equivalent work on a non-listed property and takes longer.
- Why are Kensington basement projects so heavily regulated?
- Because of the cumulative impact of basement excavation in concentrated areas. RBKC introduced strict basement policy following neighbour complaints, structural concerns, and water table impacts in streets with multiple basement conversions. Requirements now include a Basement Impact Assessment (covering hydrogeology, structural impact on neighbouring properties, and ground conditions), a Construction Traffic Management Plan, and a Construction Management Plan covering hours of work, vehicle movements, dust, and noise. Single-storey basements under existing footprint are typically permitted; multi-storey basements are restricted in most streets. Application costs and timelines are significantly higher than for above-ground extensions — Basement Impact Assessment alone adds £8,000-£20,000 in specialist surveys and reports.
- Why hire All Well for a Kensington kitchen project?
- Three reasons. First, planning experience: we handle Listed Building Consent, Section 20 leaseholder consultation, Licence to Alter on mansion flats, Basement Impact Assessment on basement projects, and Construction Management Plan applications alongside RBKC planning. We work with conservation-specialist architects and heritage consultants on every listed project. Second, full accreditation: NICEIC for electrical (BS 7671) — including concealed routing through 18-24 inch solid walls without damaging original plaster — FENSA for glazing, Gas Safe registered for boiler relocation, structural engineer calculations included, and Building Control sign-off included on every project. Third, fixed-price contracts at premium specification: the quote doesn't change unless the specification does, including all heritage materials and luxury appliances and joinery (Bulthaup, Boffi, Smallbone, Wolf, Sub-Zero). 57 verified Google reviews averaging 4.5/5. Office on Limes Avenue, SE20.
Kitchen Extensions Near Kensington
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