Home extensions
More space, the right way.
Verified Premium builders for single-storey, double-storey, wraparound and side-return extensions. One auction, one builder — never a flood of cold calls.
Recent Extension, Surrey
Single-storey rear extensions typically £55k–£140k.Recent Extension, Essex
Single-storey rear extensions typically £55k–£140k.Recent Extension, Birmingham
Single-storey rear extensions typically £55k–£140k.Anonymised recent matches.
01
What "Extension" covers
Verified Premium specialists who handle the full scope, not just one slice. One auction, one builder, one point of contact.
Single-storey rear and side-return extensions
Double-storey extensions and over-garage builds
Wraparound extensions and reconfigured ground floors
Permitted-development and full planning routes
02
What we typically include — and don't
A clear scope is the difference between a smooth project and the renovation horror story your friends tell at dinner.
Included
In scope- Architectural drawings and structural calcs
- Build, services, finishes and a typical contingency
- Optional Project Protection escrow once your builder is confirmed
Typically not included
Priced separately- Furniture, white goods, soft furnishings
- Bespoke joinery beyond a standard fit-out
- Landscaping the surrounding garden (priced separately)
03
Realistic cost range
Single-storey rear extensions typically £55k–£140k.
The Project Cost Tool gives you a postcode-adjusted range with a clear breakdown of what’s included. Use it before you talk to a builder so you walk in knowing your numbers.
04
Common questions
Direct, plain answers. No marketing copy.
How much does a typical extension cost in the UK?
A single-storey rear extension typically lands between £2,000 and £3,500 per square metre — including design, build and finishes. Use the Project Cost Tool for a postcode-adjusted range.
Do I need planning permission?
Many extensions fall under permitted development, but it depends on size, neighbours, conservation area, and listed status. Builders on Compare Builders flag this in their first conversation; lawful-development certificates are a common first step.
How long does an extension take to build?
A single-storey rear extension typically runs 10–14 weeks on site once permissions are granted. A wraparound or double-storey is more like 14–22 weeks. Lead times for design + planning add another 8–16 weeks before you start.
Ready when you are
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