House Extensions in Brent
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At Bigness Group, we design and build custom house extensions in Brent, helping homeowners across the borough unlock more space, light, and value.
From family homes in Wembley and Kingsbury to period terraces in Willesden Green and Kilburn, we deliver high-quality extensions that combine architectural precision with everyday functionality.
Our team manages the entire process — design, planning permission, engineering, and construction — ensuring your project is seamless, compliant, and beautifully built.
Design and Build Services
Our Brent specialists offer a complete design-and-build service under one contract for total peace of mind:
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Full survey, concept design, and 3D visualisations
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Planning and permitted development advice for Brent Council
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Structural design and Building Control submissions
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Kitchen, living, and open-plan interior design
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Dedicated project management and communication throughout
We handle everything in-house, ensuring efficiency, accountability, and quality control from start to finish.
Types of Extensions We Build
We construct every major form of home extension across Brent, including:
• Glass Box Extensions – Striking glass box extensions that redefine modern living.
• Modern House Extensions – Transform your home with a sleek, light-filled modern extension.
• Single-Storey Extensions – Ideal for kitchens, dining areas, or open-plan living.
• Double-Storey Extensions – Add space on both levels for bedrooms, offices, or bathrooms.
• Side-Return Extensions – Perfect for Victorian and Edwardian properties with narrow side gaps.
• Rear Extensions – Create bright and modern spaces opening onto your garden.
• Wrap-Around Extensions – Combine side and rear expansions for maximum space and light.
• Conservatories & Orangeries – Classic glazed additions for year-round use.
• Loft & Garage Conversions with Extensions – Integrated vertical or lateral expansions for full property transformation.
Construction Standards
Every Brent project follows a strict, structured process:
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Groundworks & Foundations – Excavation and reinforced bases suitable for local soil conditions.
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Structural Frame & Steel – Precision-installed RSJs and lintels for open-plan layouts.
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Walls & Roofing – Brick match, render, or cladding for seamless finishes.
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Glazing & Insulation – Energy-efficient systems meeting UK Building Regulations.
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Interior Finishes – Electricals, plumbing, plastering, flooring, and joinery.
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Inspection & Sign-Off – Building Control approval and long-term warranty.
Local Knowledge
We’re experienced with Brent Council’s planning and building control processes, including guidance for conservation areas in Queens Park, Mapesbury, and Kilburn.
Our team’s familiarity with local policies ensures quicker approvals and compliance with all planning and environmental standards.
Costs and Financing
Every extension is unique, but here’s a general guide:
| Type | Typical Cost Range (2025) |
|---|---|
| Single-Storey Extension | £45,000 – £85,000 |
| Double-Storey Extension | £75,000 – £130,000 |
| Wrap-Around Extension | £90,000 – £160,000 |
| Side-Return Extension | £40,000 – £75,000 |
💡 Factors include size, materials, access, and specification level.
We provide transparent quotes with detailed breakdowns and stage payments.
Financing options may be available through our partner lenders for eligible clients — ask our team for guidance on home improvement financing.
The Process
1. Consultation & Site Visit – We meet you on-site to discuss ideas, goals, and feasibility.
2. Design & Planning – We prepare drawings, handle permissions, and finalise the budget.
3. Construction Phase – Our project manager oversees all work, ensuring safety and communication at every step.
4. Completion & Aftercare – Once finished, we conduct final inspections and provide warranty documentation.
We also offer optional maintenance plans to keep your new space performing at its best.
Why Choose Bigness Group
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Local expertise: deep knowledge of Brent’s planning rules and property types.
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End-to-end service: one team managing design, permissions, and build.
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Certified craftsmanship: accredited professionals delivering premium results.
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Transparent costs: detailed quotations and milestone payments.
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Proven reputation: trusted across North West London for quality and reliability.
At Bigness Group, we turn renovation ideas into inspiring, functional spaces built to last.
FAQ
Do I need planning permission for an extension in Brent?
Most single-storey projects fall under permitted development, but larger or multi-level builds need planning approval. We manage this from start to finish.
How long does a Brent house extension take?
Typically 8–14 weeks for single-storey and 12–20 weeks for larger or double-storey projects.
Can you match the existing house design?
Yes — we replicate materials, rooflines, and architectural detailing for a seamless finish.
Do you work in conservation areas?
Absolutely. We have extensive experience securing approvals for period and protected properties.
Our Recent Projects in Brent
Our Brent portfolio features bright kitchen extensions in Wembley, wrap-around designs in Willesden, and full double-storey upgrades in Kingsbury. Each build showcases our attention to structural precision, light optimisation, and design harmony. Homeowners trust Bigness Group for creative, compliant, and beautifully executed extensions across Brent.
House Extensions in London by Borough
Bigness Group designs and builds bespoke house extensions across all 32 London boroughs. Our local teams understand each area’s planning rules, architectural character, and building standards — ensuring every project is delivered with precision, compliance, and style, no matter where you live in the capital.
Barking and Dagenham / Barnet / Bexley / Brent / Bromley / Camden / Croydon / Ealing / Enfield / Greenwich / Hackney / Hammersmith and Fulham / Haringey / Harrow / Havering / Hillingdon / Hounslow / Islington / Kensington and Chelsea / Kingston upon Thames / Lambeth / Lewisham / Merton / Newham / Redbridge / Richmond upon Thames / Southwark / Sutton / Tower Hamlets / Waltham Forest / Wandsworth / Westminster
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