Extensions
Single and double-storey, wraparounds and rear extensions. Steels, glazing and bifolds all priced in the quote — no provisional sums hiding surprises.
The extension you've been planning, built properly.
Stonebridge is a Guildford design-and-build firm. One team takes your project from first sketch to final snag — on a fixed quote, with one project manager you can actually get hold of.
- FMB member
- TrustMark registered
- Building in Surrey since 2011
- £5m public liability insurance
14+
Years building in Surrey
180+
Projects handed over
4.9★
Average client rating
£5m
Public liability cover
What we build
Design and build, under one roof
No juggling architects, structural engineers and trades. We handle drawings, planning, building control and the build itself — so nothing falls between the gaps.
Loft conversions
Dormer, hip-to-gable and Velux conversions. We check head heights and party wall requirements before you spend a penny on drawings.
Full renovations
Whole-house refurbishments, rewires, replumbs and reconfigurations. Ideal if you've just bought a tired Guildford semi with good bones.
Kitchens & open-plan living
Knock-throughs, kitchen-diners and broken-plan layouts. Structural calcs, building control sign-off and the kitchen fit itself, one contract.
Garden rooms
Fully insulated, year-round garden offices and studios with power, data and heating. Most fall under permitted development — we'll confirm yours does.
New builds
Single dwellings and small plots, from groundworks to completion certificate. We work alongside your architect or bring in ours.
Featured projects
Recent work around Guildford
Every project below was finished on the agreed date or earlier, and signed off by building control first time.
Rear extension
The Merrow kitchen-diner
A 6m rear extension with structural glazing and underfloor heating, opening a 1930s semi onto the garden.
“They were out of our kitchen two days earlier than promised.”
Loft conversion
The Godalming dormer
Hip-to-gable loft conversion adding a master bedroom and en-suite, with bespoke oak staircase to match the original.
“The scaffold was down before the neighbours had time to grumble.”
Full renovation
The Cranleigh farmhouse
Top-to-bottom renovation of a Victorian farmhouse: rewire, replumb, new roof, lime replastering and a reconfigured ground floor.
“One number to call for everything. That alone was worth it.”
How it works
From first sketch to handover
Consultation
We visit, measure up, talk through what you want and what the budget realistically buys. Free, and no obligation.
Fixed quote
A detailed, itemised, fixed-price quote — not an estimate that creeps. If we missed it, that's on us.
The build
Our own trades, a tidy site, and a weekly progress update with photos. Neighbours notified before we start.
Handover
Building control certificates, warranties and a snagging walk-through. We come back at six months to check on settlement.
One project manager, start to finish. You'll have their mobile number from day one.
Why Stonebridge
Checks you can actually verify
Federation of Master Builders member
Independently vetted and inspected. Our membership number is on every quote — look us up before you sign anything.
TrustMark registered
Government-endorsed quality scheme covering our workmanship, customer care and trading practices.
£5m public liability insurance
Full cover on every site, every day, plus employer's liability for our team. Certificates available before work starts.
Established 2011
Fourteen years, the same company name, the same yard outside Guildford. Most of our work now comes from past clients' streets.
Reviews
What clients say when it's done
★★★★★
“Our wraparound extension came in exactly on the quoted price. When they found rotten joists under the old kitchen floor, they showed us photos, gave us a price the same day, and kept the programme on track.”Helen & Mark D. Burpham, Guildford — wraparound extension
★★★★★
“Dan, our project manager, texted every Friday with photos and what was happening the following week. After two bad experiences with other builders, that communication was everything.”Priya S. Woking — loft conversion
★★★★★
“The site was swept and locked every single evening. Building control passed everything first visit, and the six-month check-up actually happened — they came back and eased two doors free of charge.”Graham T. Farnham — full renovation
Where we work
Guildford and the villages around it
We keep our patch deliberately small, so the project manager is never more than half an hour from your site.
- Guildford (HQ)
- Godalming
- Woking
- Farnham
- Cranleigh
- Horsham
Start your project
Tell us what you're planning. We'll tell you what it really costs.
08081 570233Monday to Friday, 8am–6pm · Saturdays 9am–1pm
Request a free consultation