Single and double storey extensions in Hayes. Trusted, professional, 30+ years' hands-on experience.
Extending a 1930s semi in Hayes is one of the most popular projects we take on. GS Renovation has over 30 years of experience building single and double storey extensions across UB3, and the generous interwar plots here often leave real room to the side and rear. We handle the design, groundworks, steel and fit-out from start to finish.

The wide plots typical of Hayes suit side-return and side infill extensions, because many 1930s semis have a gap between the house and the boundary that can be built into. A single storey rear extension opens the kitchen onto the garden, while a wrap-around scheme combines the side and rear to transform the whole ground floor. We dig and pour foundations to suit the ground, install any steel beams, then build up the walls, roof and openings.
Whether your extension is permitted development or needs a full planning application depends on the property, the size and how much has already been added. Many single storey rear extensions on these interwar plots fall under permitted development, but larger or two storey schemes, and anything near a boundary, may need permission from Hillingdon Council. We assess your home first, advise on the route, and prepare the drawings and applications accordingly.
Growing families in UB3 often want more than an extra room downstairs, so we build two storey side and rear extensions that add a bedroom or en-suite above a larger kitchen. On a 1930s semi this means matching the existing brick and roofline, tying the new structure into the old, and upgrading foundations where the extra load demands it. Building regulations cover the structure, insulation, drainage and fire safety throughout the works.
Because a second storey usually shares or sits close to the party wall with the neighbouring semi, these projects generally need Party Wall Act notices, which we serve early to keep things moving. We coordinate the structural engineer, the groundworks and the roof, then complete the full fit-out including plastering, electrics, heating and decoration. You deal with one team from the first survey to the final inspection by Hillingdon Council building control.
Families in Hayes choose GS Renovation because we manage the whole extension under one roof, from the planning route with Hillingdon Council to the party wall notices, the steelwork and the finish. Our 30+ years across UB3 mean we know how these interwar semis are built, so we tie new to old cleanly and keep the site tidy while you live in 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
We price each Hayes project individually, because the cost of house extensions depends on far more than floor area. After a free survey you receive a clear written breakdown with no hidden extras. Call 07472 424 226 or email info@gsrenovationltd.co.uk. 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.
We will give you an honest timescale for house extensions in Hayes after surveying your home. Most projects run on a clear weekly programme, and we tell you up front about any lead times on materials or approvals.
Because we manage every trade in-house, your Hayes project stays consistent and accountable from first fix to finish. Add transparent pricing, full insurance and real aftercare, and it is easy to see why Hayes clients recommend us.
Many single-storey rear extensions in Hayes 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 Hayes's homes are 1930s and interwar properties, and we renovate them regularly. We plan each house extensions around their particular characteristics, such as cavity walls, regular original layouts and the generous plots that suit extending, so the result suits the building and meets building control.
It depends on the size and your property. Many single storey rear extensions on the generous Hayes plots are permitted development and only need building regulations approval, but larger, side or two storey schemes, or homes that have already been extended, may need a planning application to Hillingdon Council. We check your specific situation before we design anything and handle whichever route applies.
Yes, Hayes is one of our core areas. We work on every street and the UB3 area and across the wider West London, so wherever your home is, call 07472 424 226 and we will confirm we can help.
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 Hayes. 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 Hayes and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in Hayes.
Get Your Free Quote