House Extensions in Bexley
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At Bigness Group, we design and build bespoke house extensions in Bexley, helping homeowners expand their living space and elevate property value with precision and style.
From Victorian terraces in Bexleyheath to detached family homes in Sidcup and Welling, we deliver extensions that enhance comfort, light, and functionality — all built to London’s highest construction standards.
We handle the entire journey — planning, design, engineering, and build — giving you a seamless experience from concept to completion.
Design and Build Services
Our Bexley design-and-build team manages your entire project in one streamlined process:
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Measured survey, drawings, and 3D visualisations
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Planning and permitted development advice
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Structural calculations and Building Control coordination
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Kitchen, living, and interior redesigns
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Dedicated project management with transparent timelines
This integrated approach ensures your extension runs efficiently, with minimal stress and maximum quality.
Types of Extensions We Build
We construct every major type of residential extension across Bexley, 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 Bexley project is built under strict quality control and structural safety:
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Groundworks & Foundations – Engineered to suit local soil and drainage conditions.
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Steel & Framing – RSJs and supports for open-plan layouts.
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Walls & Roofs – Brick match, render, or cladding with warm-roof insulation.
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Glazing & Energy Systems – Part L–compliant, energy-efficient materials.
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Interior Finishes – Bespoke joinery, plasterwork, plumbing, and electrics.
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Final Inspection – Building Control sign-off and warranty certification.
Local Knowledge
We understand Bexley Council’s planning requirements, including conservation areas in Old Bexley and Sidcup.
Our local experience ensures your extension gains fast approvals, complies fully with Building Regulations, and enhances your home’s character and value.
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: extensive knowledge of Bexley’s planning and architectural landscape.
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End-to-end delivery: one team managing design, permissions, and build.
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Accredited professionals: all work certified and compliant with UK standards.
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Transparent pricing: fixed quotations and milestone payments.
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Proven results: trusted by homeowners across South East London.
Bigness Group delivers more than extensions — we create spaces that elevate everyday life.
FAQ
Do I need planning permission for an extension in Bexley?
Many smaller extensions fall under permitted development, but double-storey or wrap-around builds often require planning. We handle all applications for you.
How long does a typical extension take to build?
On average, 8–14 weeks for single-storey and 12–20 weeks for larger extensions.
Do you work with modern and period properties?
Yes — we tailor our approach for both contemporary and heritage-style homes across the borough.
Can you include kitchens or loft conversions in the same project?
Absolutely. We regularly integrate multiple elements for complete home transformations.
Our Recent Projects in Bexley
Our recent work across Bexleyheath, Welling, and Sidcup showcases how well-planned extensions transform family homes. From bright kitchen extensions with rooflights to multi-level builds with integrated conversions, each project reflects Bigness craftsmanship and design integrity. We take pride in helping Bexley homeowners expand beautifully, sustainably, and smartly.
House Extensions in London by Borough
Bigness Group delivers expertly designed and built house extensions across every London borough. Our local teams understand area-specific planning rules, architectural styles, and Building Control requirements — ensuring every project is compliant, efficient, and beautifully integrated with its surroundings. Bigness Group designs and builds custom house extensions throughout London’s 32 boroughs. Our local specialists know each area’s planning rules, property styles, and Building Control standards—so every extension fits perfectly, meets regulations, and adds lasting value.
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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