House Extensions in London: Side Return, Rear, Double Storey & Wrap-Around
We can help with design and build house extensions across London- adding space, light, and better flow, from kitchen-diners to extra rooms and full open-plan ground floors. We manage the project end-to-end, coordinating trades and keeping the build organised from foundations through to finishing.
Extension types we deliver
Rear extensions: the most common way to expand a kitchen/living area into the garden. Single-storey rear from £45,000, typically 10–14 weeks on site.
Side return extensions: ideal for Victorian/Edwardian terraces to use the narrow side alley space. From £40,000, typically 10–14 weeks on site.
Wrap-around extensions: a rear extension combined with a side return to create an “L-shape” footprint and maximise space.
Single- and double-storey extensions: depending on the extra space you need and what planning allows. Double-storey from £110,000, typically 16–22 weeks on site. As a rule of thumb, extensions start from around £2,200 per m² including VAT.
Planning and Building Regulations
Some single-storey rear extensions may be possible under permitted development (subject to size limits and conditions), while larger or more complex extensions often require planning permission. Building Regulations approval still applies, covering key areas like structure, insulation/energy performance, drainage, and safety.
What’s included
We typically handle: groundworks and foundations, structure and steelwork for open-plan layouts, roofing and windows/doors, first fix plumbing/electrics, plastering, flooring, kitchen/bathroom fit-out (if included), and final decoration. The exact scope depends on whether you want a shell build or a complete “ready to live in” finish.
Get a quote
Contact us to arrange a site visit and quotation for your extension. If you share your postcode, photos of the rear/side, and what you want to achieve (bigger kitchen, utility, extra bedroom), we can advise the best extension type and likely next steps. Guide prices include VAT; your fixed price comes in the itemised written quote after a free site visit.
07903854379 02074762770
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