Single and double storey extensions in Chiswick. Trusted, professional, 30+ years' hands-on experience.
GS Renovation designs and builds extensions across Chiswick, working with the side returns and rear closet wings that define W4's Victorian and Edwardian terraces. With over 30 years in the area, we take on rear, side-return, wrap-around and double-storey projects from foundations to final fit-out, one accountable team throughout.

The classic Chiswick project is filling the side return, the narrow strip beside the rear closet wing, to widen a cramped galley kitchen into an open-plan space that runs the full width of the house. We dig and pour foundations to suit the ground and any nearby trees, build the walls, and install the steel beams that carry the original rear wall once it comes out. Rooflights over the new zone bring daylight deep into the plan.
Because these are period terraces, we match brick and detailing where it shows and think hard about how the new roof meets the existing closet wing. Every W4 house is slightly different in plot width and orientation, so we plan drainage, party wall bearings and glazing around your specific layout. The result reads as part of the house rather than a bolt-on, with the structure and finishes handled together.
Some Chiswick extensions fall under permitted development and some need a full planning application to Hounslow Council, and which one applies depends on your property. Single-storey rear extensions within the permitted size limits often proceed under permitted development, but if your home sits in a conservation area, has been extended before, or you want a larger or double-storey scheme, a planning application is usually required. We advise honestly at the survey stage.
Whichever route applies, the build itself must meet building regulations, and where you extend against a shared boundary the Party Wall Act brings notice duties with your neighbours. We prepare and coordinate the drawings, handle the council submission or the certificate of lawful development, and manage the party wall notices. That way the paperwork and the construction stay joined up rather than becoming your problem to chase.
Chiswick clients choose GS Renovation because we run the extension end to end, foundations, steelwork, roof, party wall coordination and the full fit-out, with clear advice on whether you need planning or can build under permitted development. Three decades on W4 terraces means we understand side returns and closet wings and deliver a space that belongs to the house.
George was brilliant. Lovely bloke, very reasonably priced and a perfectionist to boot. He completed our small kitchen renovation with care and great attention to detail. I've already recommended him to others.
Splendid job on our new kitchen refurb, including new flooring, moving the services, installing RSJ and preparing space for new back doors… George was always friendly, communicative and has an excellent attention to detail, ensuring everything is finished to a high standard.
Giorgio is an excellent and intelligent workman, and with very reasonable prices!… He paid a lot of attention to detail that is not common at all, and the final result was immaculate. Highly recommended!
FAQ
Pricing house extensions in Chiswick comes down to the size of the job, the specification you choose and the condition of the property. Rather than guess, we survey and give you a fixed, itemised quote you can rely on. Call 07472 424 226. As a rough guide, house extensions in London typically starts from roughly £40,000 for a single-storey rear extension and rises with size and specification (indicative London ranges, MyBuilder and Checkatrade, 2026). Your figure depends on the size, specification and condition of the property, which is why we survey before quoting.
A straightforward Chiswick project can be done in a couple of weeks, while a larger house extensions with structural work runs longer. We set out a realistic, stage-by-stage programme before we begin so there are no surprises.
Chiswick homeowners choose GS Renovation for reliability and quality. We are fully insured, building control compliant where needed, and bring over 30 years of hands-on experience to every house extensions project, with a single point of contact throughout.
Many single-storey rear extensions in Chiswick fall under permitted development, but side returns, double-storey extensions and work in conservation areas usually need full planning permission. We assess your property and manage both the planning application and building control.
Yes. A large share of Chiswick's homes are Victorian and Edwardian terraced properties, and we renovate them regularly. We plan each house extensions around their particular characteristics, such as solid brick walls, rear closet wings, side returns and original period features, so the result suits the building and meets building control.
It depends. Many single-storey rear and side-return extensions in W4 fall under permitted development, but if your terrace is in a conservation area, already extended, or you want a larger or two-storey scheme, a planning application to Hounslow Council is likely. Either way the build needs building regulations approval, and a shared boundary brings party wall notices. We assess your specific property and handle the route that applies.
Yes. We work throughout Chiswick and the W4 area, as well as the surrounding parts of West London. Contact us on 07472 424 226 to confirm we cover your street.
Every Service, One Team
The same trusted team, 30+ years' hands-on experience and free, no-obligation quotes apply to every GS Renovation service in Chiswick. Explore what else we do locally:
Steel beam installation, RSJ and structural alterations.
Safe load-bearing wall removal with steel beam support.
Structural alterations, new openings and steel support.
Chimney breast removal with gallows bracket or beam support.
Open-plan kitchen, diner and living conversions.
Full refurbishments and whole-house renovations.
Bespoke kitchen design and installation.
Luxury bathroom and wet-room refurbishment.
Same Service, Nearby Areas
We carry out house extensions across Chiswick and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in Chiswick.
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