The Design & Build Company That Actually Belongs Here
LCCL Construction isn't a company that "covers" North London from an office across the city. We're based in Finchley N3. Our team lives and works in these postcodes. We've been building across N, NW, and EN areas for over 20 years — and that proximity means something practical: your project manager can be on site in minutes, not hours.
North London's housing stock is what we know best. The 1930s semis of Woodside Park with their hipped roofs begging for hip-to-gable conversions. The Edwardian terraces of Crouch End and Muswell Hill where side returns and rear extensions transform cramped kitchens into open-plan living. The Victorian villas of Highgate and Hampstead where conservation area sensitivity isn't optional. The postwar homes across Barnet and Enfield where practical conversions deliver the best value per pound spent.
We don't just work in North London — we've shaped hundreds of homes across it. LABC Building Excellence Award Winners 2024. Over 200 reviews at 4.7/5. NFB members. LABC Registered Partners. Every project delivered by one in-house team: architects, engineers, builders, project managers.
Areas We Serve Across North London
We have dedicated area pages with local pricing, planning guidance, and project details for: Barnet, Finchley, Hendon, Muswell Hill, Edgware, Enfield, Highgate, Crouch End, Hampstead, Islington, Camden, and Stoke Newington. Each page reflects genuine knowledge of that area's housing stock, planning authority, and conservation areas — because we work there regularly, not occasionally.
Our Services
Design and build under one roof, Architecture, planning, construction, and finishing — managed by one team, from start to finish.
- HOUSE EXTENSIONS
House Extensions Across North London
Extension possibilities vary enormously across North London depending on property type, plot size, and planning context. The generous plots in Barnet and Enfield allow for substantial wraparound and double-storey extensions that would be impossible on the tighter sites of Islington or Camden. Victorian terraces across Crouch End, Stoke Newington, and Muswell Hill respond brilliantly to the side return and rear extension combination that opens up the ground floor. Conservation areas in Hampstead, Highgate, and Islington demand more sensitive design but don't prevent ambitious projects.
What stays consistent across every North London extension is our approach: in-house architecture designed for buildability, structural engineering that anticipates problems before they happen, and construction quality recognised by the LABC Building Excellence Award. Whether your extension costs £40,000 or £250,000, the same team delivers it to the same standard.
Extension Costs Across North London
Rear Extensions — £45,000–£120,000. The most achievable extension type across all areas.
Side Return Infills — £35,000–£75,000. Transforms the ground floor of Victorian terraces.
Wraparound Extensions — £60,000–£120,000. Side and rear combined for maximum transformation.
Double-Storey Extensions — £90,000–£250,000+. For properties with sufficient plot space.
What Is Included
All prices include: architecture, structural engineering, planning applications, all construction, project management, building control via LABC, and 10-year LABC warranty. All-inclusive quote. Call 020 8037 7332.
- LOFT CONVERSIONS
Loft Conversions Across North London
North London's varied housing stock creates different loft conversion opportunities in every neighbourhood. The hipped roofs on 1930s semis in Barnet, Hendon, Edgware, and Finchley are ideal for hip-to-gable conversions — our most-requested project type. The steeply pitched Victorian and Edwardian roofs across Muswell Hill, Crouch End, Highgate, and Stoke Newington suit rear dormers and mansard conversions. The grander properties in Hampstead and Islington often require conservation-sensitive designs with flush rooflights or carefully proportioned rear dormers.
Most loft conversions in North London outside conservation areas qualify under permitted development. Within the conservation areas that cover much of Hampstead, Highgate, Muswell Hill, and Islington, planning permission is required — and that's where our architects' local experience proves its value.
Loft Conversion Costs Across North London
Rear Dormers — £42,000–£90,000. The most popular option across all North London areas.
Hip-to-Gable — £48,000–£95,000. Ideal for 1930s semis in Barnet, Hendon, Edgware, and Finchley.
Mansard Conversions — £60,000–£110,000+. Maximum space for terraced properties.
L-Shaped Dormers — £55,000–£100,000. For end-of-terrace properties combining rear and side elements.
What Is Included
All prices include: architecture, structural engineering, scaffolding, all construction, staircase, insulation, electrics, en-suite plumbing, building control via LABC, project management, and 10-year LABC warranty. Call 020 8037 7332.
- RENOVATIONS
Renovations Across North London
Renovation work across North London ranges from targeted kitchen and bathroom upgrades to complete whole-house refurbishments that strip a property back to its shell. The scope depends on the property and the homeowner's ambition — but the approach is always the same: one team managing design, structural work, and construction under a single contract.
North London's period properties often need structural reconfiguration alongside cosmetic upgrading. Opening up ground floors with steel beams, creating en-suites from box rooms, upgrading electrics and plumbing that haven't been touched in decades, and restoring original features that previous owners covered over. For listed buildings in Hampstead and Highgate, renovation work may require Listed Building Consent — our architects manage this alongside the construction programme.
Typical renovation costs: kitchen installations £25,000–£85,000, bathroom renovations £12,000–£40,000, structural reconfiguration £6,000–£20,000, whole-house refurbishment from £85,000 upward depending on property size and specification.
- ARCHITECTURE
In-House Architecture for North London Properties
Our architects submit planning applications across every North London borough: Barnet, Haringey, Camden, Islington, Hackney, Enfield, and more. Each authority has different policies, different officer expectations, and different conservation area requirements. An architect who works across all of them understands not just how to design well, but how to get approvals efficiently — which designs satisfy which planning teams, which supporting documents are required, and where pre-application advice is worth pursuing.
The integrated design and build model means our architects design with construction costs and buildability in mind from the first sketch. There's no gap between what the architect draws and what the builder can deliver for the budget. That single point of accountability eliminates the disputes, redesigns, and cost surprises that plague the traditional architect-then-builder model.
Every North London project includes: measured survey, concept designs, 3D visualisations, construction drawings, planning applications or LDCs, structural engineering, and building regulations via LABC. All included in your quote.
- LOCA PLANNING EXPERTISE
Planning Across North London
Borough Coverage
North London spans multiple planning authorities, each with distinct policies and conservation area coverage. Our architects submit regularly to all of them. London Borough of Barnet has 16 conservation areas, 10 with Article 4 Directions, covering Barnet, Finchley, Hendon, Edgware, Mill Hill, Totteridge, and Hampstead Garden Suburb. London Borough of Haringey has conservation areas in Muswell Hill, Crouch End, Highgate (east), and Hornsey.
Inner North London Boroughs
London Borough of Camden has extensive conservation area coverage including Hampstead, Highgate (west), Primrose Hill, and Kentish Town with basement development policies. London Borough of Islington has over 40 conservation areas with strict design expectations. London Borough of Hackney has conservation areas in Stoke Newington and Newington Green.
Outer North London
London Borough of Enfield has conservation areas in Bush Hill Park, Enfield Town, and Winchmore Hill. Generally supportive of residential extensions within PD limits.
Typical Planning Timescales
Householder applications across all boroughs target 8-week decisions. We handle the complete planning process for every project.
Permitted Development
Standard PD rights apply outside conservation areas across most North London boroughs. Within conservation areas, rights are restricted and planning permission is usually required. We assess each property individually and recommend the fastest route to approval.
Building Control
All LCCL projects are managed through LABC building control. Inspections at each key stage ensure compliance with Building Regulations. At completion, you receive a building control completion certificate and optional 10-year LABC warranty.
Frequently Asked Questions
Where is LCCL based?
Our office is in Finchley N3, in the heart of North London. Most North London addresses are within 15–25 minutes of us.
Which areas do you cover?
All of North London including Barnet, Finchley, Hendon, Muswell Hill, Edgware, Enfield, Highgate, Crouch End, Hampstead, Islington, Camden, Stoke Newington, and surrounding areas. We have dedicated pages for each area with local pricing and planning information.
How much does an extension cost in North London?
Costs vary by area and project type: rear extensions £45,000–£120,000, side returns £35,000–£75,000, double-storey £90,000–£250,000+. All prices include architecture, engineering, planning, construction, and 10-year LABC warranty. See our area pages for location-specific pricing.
What's included in your price?
Everything: architecture, structural engineering, planning applications, all construction, project management, building control via LABC, and 10-year LABC warranty. Transparent pricing with no hidden extras. Final costs confirmed once designs and structural requirements are agreed.
How do I get started?
Call 020 8037 7332 or book a free consultation. We visit your property, discuss your ideas, and provide honest advice. Free, no obligation.
Areas We Cover
Based in Finchley N3, serving London and Hertfordshire.
North London and Hertfordshire
Barnet | Finchley | Hendon | Muswell Hill | Edgware | Enfield | Borehamwood | Potters Bar | Watford | St Albans
Across London
Hampstead | St Johns Wood | Islington | Kensington & Chelsea | Fulham | Clapham | Richmond | Putney & Wandsworth | Crouch End | Stoke Newington | Highgate | Ealing | Notting Hill | Camden | Queens Park