House Extensions in Croydon

At Bigness Group, we design and build premium house extensions in Croydon, helping homeowners expand their living space, improve comfort, and add lasting value.
From Edwardian houses in South Croydon to modern properties in Purley and Thornton Heath, we deliver bespoke extensions that enhance both form and function.

Our experienced team manages every phase — from concept and planning to engineering and construction — ensuring your extension is delivered on time, within budget, and built to last.

Design and Build Services

Our Croydon design-and-build team handles your project from start to finish:

• Architectural design, surveys, and 3D visualisations
• Planning and permitted development advice through Croydon Council
• Structural calculations and Building Control approvals
• Interior layout, kitchen, and lighting design integration
• Dedicated project management and transparent communication

This integrated approach ensures you get one cohesive process, one accountable team, and one exceptional result.

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 Bigness project in Croydon is built under strict quality and compliance standards:

1. Groundworks & Foundations – Engineered for Croydon’s clay and mixed soil conditions.
2. Structural Framework – RSJs and steel beams installed for safe, open layouts.
3. Walls & Roofing – Matching brickwork, warm roof systems, and energy-efficient finishes.
4. Glazing & Insulation – High-performance materials meeting latest Part L standards.
5. Interior Fit-Out – Plumbing, electrics, plastering, flooring, and decoration.
6. Inspection & Certification – Building Control approval and structural warranties provided.

Local Knowledge

We have extensive experience with Croydon Council’s planning requirements, from extensions in conservation zones to developments within Article 4 areas.
Our understanding of local building policies, materials, and neighbourhood aesthetics ensures your extension complements its surroundings and gains approval smoothly.

Costs and Financing

Every extension is unique, but here’s a general guide:

💡 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.