Home Extensions · Surrey · Est. 2012

Built Right.
On Time. On Budget.

Hartley Extensions builds single and double storey extensions, loft conversions, and full renovations across Surrey. Every project managed personally by founder James Hartley — same team, from planning permission to final handover.

Hartley Extensions
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£25M+ Total Project Value
120+ Extensions Built
12 Years In Surrey

What We Build

From a single-storey rear extension to a whole-home renovation, every project is managed personally from planning application through to final handover.

Single storey extension project Double storey home extension Kitchen extension build Loft conversion project

Selected Work

Open-plan living and dining extension with large glass wall in Esher
Modern open-plan kitchen and living extension with garden view in Cobham
Spacious modern kitchen extension interior in Woking
Contemporary kitchen renovation with wooden cabinetry and stainless appliances in Reigate
Warm loft conversion bedroom with brick wall and timber ceiling in Leatherhead
Converted attic studio space with skylights and exposed brick in Dorking

Proudly building across Surrey

★★★★★5.0 on Google
Working with Hartley was the best decision we made. They turned our cramped Victorian terrace into an open, light-filled home. The attention to detail is extraordinary.
Mr & Mrs Pemberton, Weybridge
Our kitchen extension was completed on time and on budget. The team were clean, professional, and the quality is impeccable. We would not hesitate to use Hartley again.
James H., Guildford
We have had three friends use Hartley since our loft conversion. That says everything you need to know about the quality of their work and the people behind it.
Claire & Tom R., Dorking

Free site visit. No obligation.

We come to you, assess the property, and give you an honest view of what's possible and what it costs.

Book a Site Visit

How Every Project Runs

From the first call to the moment you move back in, you work with the same team throughout. No sub-contractors handed the job halfway through.

Initial Consultation

We visit the property, listen to what you want to achieve, and walk through what is feasible. No obligation, no pitch. Just an honest conversation about your home.

Design & Planning Permission

Our in-house design team produces drawings, handles the planning application, and manages all communication with the local authority. You approve every stage before we proceed.

Build Begins

A dedicated site manager oversees your project from day one. You receive weekly progress updates, and we are accessible by phone at any point throughout the build.

Project Completion

A final walkthrough with your project manager to sign off every detail before we hand over the keys. All guarantees, certificates, and documentation are provided on the day.

About Hartley

Built on a Straightforward Principle

Hartley Extensions was founded in 2012 by James Hartley, a structural engineer who spent a decade working on commercial construction and decided there was a better way to build homes. The company is built around the belief that a homeowner deserves the same level of precision and communication that a commercial client expects.

Based in Guildford, we work across Surrey and the surrounding area. Over 120 projects later, the business is still run personally by James. Every client has his direct number, and he visits every site at least once a week throughout the build.

Hartley Extensions team working on a kitchen extension build

Common Questions

Do I need planning permission for a home extension in Surrey?

Many single-storey rear extensions fall under Permitted Development rights — no planning application needed. Larger or two-storey extensions typically require full planning permission. Hartley handles the entire planning process in-house, including all drawings and council communication.

How long does a home extension take to build?

A single-storey extension typically takes 10–16 weeks on site. Double-storey extensions run 16–24 weeks. Loft conversions average 8–12 weeks. Timelines cover structural work, first fix, plastering, second fix, and decoration — and are agreed in writing before the build starts.

How much does a home extension cost in Surrey?

Single-storey rear extensions typically start from £80,000. Double-storey extensions from £140,000. Loft conversions from £55,000. Every project is different — after the free site visit, Hartley provides a detailed fixed-price quote with no hidden costs.

Will the same team be on site throughout the build?

Yes. Hartley does not subcontract mid-project. You work with the same team from groundworks to completion, with a dedicated site manager on site daily and James Hartley visiting every week. You have his direct number throughout.

Start Your Project

Tell us about your home and what you want to change. We will come to you, take a proper look, and give you an honest view of what is possible.

Phone 07426 937381
Area Surrey & surrounding counties
Hours Monday to Friday, 8am to 6pm
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