Double Storey House Extensions in London
Double your living space with a two-storey extension. Award-winning architectural design, planning permission, and full project management.
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Double Storey House Extensions in London
A double storey extension adds two floors of new living space, making it one of the best-value investments you can make in your home. Crown Architecture designs striking double storey extensions that enhance both function and aesthetics.
Common configurations include rear double storey extensions that add a ground floor kitchen/diner and first floor bedroom or bathroom. Our architects ensure your extension integrates beautifully with your existing home and complies with all planning policies.
Why Build a Double Storey Extension?
- Maximum space gain per £ spent on construction
- Adds 2–3 extra rooms in a single project
- Significantly increases property value
- Often permitted development (subject to size)
Double Storey Extension Typical Costs
- Architect fees: from £3,500
- Construction: from £55,000 for a standard 4m × 4m two-storey rear extension
- Planning application: included in our full service
- Building regulations: included in our full service
What Our Clients Say
“Crown Architecture made the entire process stress-free. From first consultation to planning approval took just 9 weeks. Exceptional service.”
“Professional, responsive, and incredibly knowledgeable. Our project came in on budget and the design exceeded our expectations.”
“Got planning permission in 8 weeks — we’d been refused before with a different architect. Crown Architecture understood exactly what the council wanted.”