Written by Mark Reid,
Trades Editor ·Verified 14 September 2026
Stevenage is an odd mix when it comes to housing stock, and that shapes what you'll need from a builder. You've got the original New Town estates around Bedwell, Shephall and Chells with their concrete and steel-frame construction from the post-war building boom, alongside newer developments in Great Ashby and Symonds Green built with fairly standard timber-frame and brick methods. Then there's the older parts of Old Town, where Victorian terraces and cottages bring their own quirks, solid walls, no cavity, sometimes dodgy foundations on the clay soil that's common across Hertfordshire. A builder who's worked across all these areas will know that a loft conversion in a 1960s semi needs different thinking to underpinning a Victorian terrace near the High Street. Location matters too. Stevenage sits close enough to London that some homeowners want London-standard finishes without the London prices, and there's steady demand for extensions and garden rooms as families outgrow their space rather than move.
The businesses featured here are pulled from public business listings and ranked mainly by their review rating and the number of reviews they've built up, with a small boost given to those with a working website and phone number, since that's a basic sign a business is easy to reach. We also check each business's homepage to confirm builders work is genuinely what they do day to day, which stops general handymen or unrelated trades slipping onto this list. Listings flagged as permanently closed get removed automatically, so you're not looking at businesses that no longer exist. Where you spot a Trust Verified badge, that business has gone through our fuller verification process, covering trade qualifications and accreditations, public liability insurance, trading history, customer review history and registered company details. Our How We Verify page explains exactly what that involves. For any business without that badge, we'd say do those checks yourself before booking, since we haven't confirmed them at that level.
Before you commit to anyone, ask to see their public liability insurance certificate and check whether they're registered with a trade body such as the Federation of Master Builders. For anything involving gas or a boiler, confirm Gas Safe registration and ask for the licence number so you can look it up yourself. Get a written quote that breaks down labour, materials and any allowance for skip hire or scaffolding, and be wary of anyone who wants a large deposit upfront before work has even started. Getting two or three quotes for the same job is standard practice, not overkill, it'll show you quickly if one price is out of step with the others. Ask for photos of recent local jobs, ideally something similar in scale to what you need, whether that's a rear extension in Pin Green or a kitchen strip-out in Broadwater.
How We Select & Rate The Best Builders in Stevenage
Rankings are driven by review rating and review count from public business listings, with a small lift given to businesses showing a working website and phone number. We check each business's homepage to confirm builders work is what they primarily offer, which keeps unrelated trades off this page. Listings flagged as permanently closed are removed automatically. Businesses marked Trust Verified have additionally passed our full verification, covering trade qualifications and accreditations, public liability insurance, trading history, customer review history and registered company information; see our How We Verify page for full details. Other businesses listed have not been independently verified by us, and their inclusion isn't an endorsement. Always carry out your own checks before hiring.
Recommended and Featured listings are paid placements, so a business's fee affects whether and where it appears. Every other listing is ranked on rating and review count from third-party business listings. How we rank & verify →
Period properties around Stevenage often need careful attention to match existing brickwork and layouts, and Vines Construction Ltd works on this type of renovation alongside extensions and refurbishments for local homes. The firm has built a strong local reputation, reflected in a five star rating from 45 reviews. Work is arranged directly with clients rather than through third parties.
Load-bearing wall removal, RSJ installations and structural openings are the core work at Wall Away Ltd, a Stevenage builder also covering self-build extensions and conservatory integration. The firm carries a five-star Google rating from 44 reviews, reflecting consistent work across SG1 and the surrounding area.
A clean run of 43 reviews has earned Built Trust a perfect five-star average, an uncommon result in the building trade. Based in Stevenage, the firm takes on general building work for local homes, with the consistency of feedback suggesting steady workmanship rather than one-off praise.
Building and landscaping work in Stevenage is handled by Vantage Landscaping, covering groundwork, patios and garden structures alongside general construction tasks. Sixteen reviews on Google have averaged a perfect five, a consistent record for a firm operating across the local area. Enquiries are typically for both hard landscaping and smaller building jobs.
Rated 4.9 out of 5 by local clients, Conserv-a-tech operates as a building firm in Stevenage, covering general construction and property improvement work. The high rating points to consistent workmanship across a residential customer base in the area.
Ground remediation, piling platforms, and soil stabilisation sit at the core of City Grey Limited's work, alongside basement construction, underpinning, and concrete framing. The company operates from Stevenage, taking on geotechnical and structural groundwork across the region. A rating of 5.0 on Google, drawn from ten reviews, reflects consistent feedback on a technically focused range of civil engineering and building services.
Residential extensions, kitchen fitting, and wood flooring installation sit alongside commercial refurbishments in the portfolio of The Property Refurb Co, a building firm based in Stevenage. Smaller scope work, including tiling, shower screen installation, and false wall construction, is also offered. The company holds a five-star Google rating from ten reviews.
Ibuildup Ltd works mainly on older properties around Stevenage, handling extensions, renovations and structural alterations that require care with existing brickwork and layouts. The firm has built a small but consistent record locally, holding a 5 rating from 9 reviews. Work is arranged through direct enquiry via its website.
Groundworks, extensions, and new-build construction form the core offer at C Jennings Building Ltd, a Stevenage-based contractor operating across the surrounding area. The company holds a five-star Google rating from its reviewers. All work is carried out under the C Jennings Building name, with enquiries handled directly through the company website.
A perfect 5-star record across seven reviews sets TPS Groundwork & Construction Ltd apart among Stevenage builders. The firm covers groundwork and general construction projects, working with clients across the town. Its website outlines further details for those wanting to enquire about upcoming building work.
General building work in Stevenage covers everything from extensions to structural alterations and renovation projects. ShellCo Ltd works with homeowners and landlords across SG2 and the surrounding area, managing jobs from initial groundwork through to finishing. Projects are scoped and organised directly with clients rather than through subcontracted layers.
Building work across Stevenage is handled by Edis Construction, covering extensions, renovations and general contracting for domestic and commercial clients. Work is organised directly with clients from initial planning through to completion, with jobs scoped to the property rather than a fixed template. Enquiries are taken via the company's website.
Transparency notice: Recommended and Featured listings are paid placements, so a business's fee affects whether and where it appears. All other listings are ranked by a combined score drawn from ratings and review counts published on third-party business listings, plus basic completeness signals such as a working website and phone. A Trust Verified badge means we have independently checked that business's documents; businesses without it have not been independently verified by us. How we verify →
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It depends heavily on the job. A single-storey rear extension typically runs from around £1,500 to £2,200 per square metre depending on finish, so a modest 15 square metre extension might land somewhere between £25,000 and £35,000 including materials. Smaller jobs like a garden wall or repointing a chimney could be a few hundred pounds, while a loft conversion in Stevenage generally sits between £35,000 and £50,000 depending on whether it's a simple rooflight conversion or a full dormer. Prices vary by builder availability, time of year and how complex the access is. Getting two or three written quotes for the same specification is the best way to see what's reasonable.
Do I need planning permission for an extension in Stevenage?
Many single-storey rear extensions fall under permitted development rights, meaning you won't need full planning permission, but there are limits on size, height and how close you can build to a boundary. Stevenage Borough Council's planning department can confirm whether your specific plans qualify, and it's worth applying for a Lawful Development Certificate even under permitted development, since it gives you paperwork to show future buyers. If your property is in a conservation area, such as parts of Old Town, the rules are stricter, so check before any building work starts.
How long does a typical extension or renovation take?
A single-storey extension usually takes between eight and fourteen weeks once work actually begins, though groundworks, weather and getting the right building control sign-offs can push this out. A loft conversion tends to take six to ten weeks. Kitchen renovations vary a lot depending on whether structural walls are involved, but two to four weeks is common for a straightforward refit. Ask your builder for a realistic timeline in writing before work starts, including what happens if delays occur, so you both know what's expected.
Should I use a builder registered with a trade body?
It's worth it where possible. Membership of the Federation of Master Builders or similar bodies usually means the builder has been vetted to some degree and offers a form of warranty or dispute resolution if things go wrong. It's not a guarantee of quality, but it gives you somewhere to turn if a job isn't finished properly. Combine this with checking reviews and asking to see previous work in person rather than relying on photos alone.
What's the difference between a quote and an estimate?
A quote is a fixed price for the work described, and a reputable builder should stick to it unless you change the scope of the job. An estimate is a rough guide and can change once work begins, particularly if unexpected issues turn up, like discovering old pipework or a damp problem behind a wall in an older Old Town property. Always ask which one you're being given in writing, and get any variations to the price agreed in writing too before work continues.
How do I check a builder is right for my job before hiring them?
Start by asking for their public liability insurance certificate and checking it's current, not just taking their word for it. Ask for addresses of recent jobs similar to yours and, if possible, speak to those previous customers directly rather than relying only on online reviews. Check Companies House if they're a limited company, to see how long they've been trading. For gas or boiler work, verify their Gas Safe registration number yourself on the Gas Safe Register website. Finally, get everything in writing, quote, start date, payment schedule and what happens with any changes, before you sign anything or hand over a deposit.
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