From £22,280
Trusted and professional extension builder in HP18. Experienced in all extension buildering work and keeping within budget and on quote. BUILDRIGHT...
From £22,128
Relax... you have found a reliable extension builder in HP18. Trew Builders is a friendly and reliable company based in HP18 who consider no job as...
From £22,168
Platinum Build Ltd are here to help customers who need an Extension Builder in HP18. We offer a competitive rate to complete all your extension bui...
From £22,256
Thame Builders Ltd: Your Local Professional Building Experts.\n\nAt Thame Builders, we pride ourselves on being more than just a construction compa...
From £22,304
done lots of extensions and refurbishment of houses from 2004-2012 in london from 2012 till now in oxfordshire area.
From £22,448
Trusted and professional extension builder in HP18. Experienced in all extension buildering work and keeping within budget and on quote. C HORWOOD ...
From £22,240
AMG Roofing (Bucks) Ltd is owned by Ashley Gibson, a small, friendly, family run business that began in 2020, as a result of the Pandemic and an ac...
From £22,160
D M B E BUILDPLUS is an established and experienced local extension builder in HP18. Please contact us for a free, no obligation quote and competit...
From £22,080
We are ADC Landscaping & Gardening, owned and run by Ashley Collier. We are a family business based in Aylesbury, Buckinghamshire, and cover all as...

A flat roof extension ranges from the cheapest of £22,080 (ADC Landscape And Garden Maintenance Contractors based in HP21) to the dearest of £22,448 (C HORWOOD CONSTRUCTION based in HP19), but these are just estimates. While they give you an idea of who will be better value, the best way to compare costs is to get real quotes.
Find out how much your flat roof extension will cost in HP18 by posting a job with HaMuch. We'll send it to extension builders in HP18.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Build A Flat Roof Extension near Aylesbury Vale | £36 | £246 |
| Build A Flat Roof Extension near Aylesbury | £42 | £270 |
| Build A Flat Roof Extension near Bicester | £35 | £249 |
| Build A Flat Roof Extension near Cherwell | £35 | £249 |
| Build A Flat Roof Extension near Oxford | £37 | £265 |
| Build A Flat Roof Extension near South Oxfordshire | £36 | £253 |
| Build A Flat Roof Extension near Wycombe | £39 | £271 |
| Build A Flat Roof Extension near Leighton Buzzard | £38 | £270 |
| Build A Flat Roof Extension near High Wycombe | £39 | £272 |
| Build A Flat Roof Extension near Hazlemere | £40 | £272 |
Whether you’re looking to extend your kitchen with a side return extension or you want to convert your basement into a liveable space, read our cost guides to get an idea of how much each project costs before getting a more accurate quote from our database of reliable tradespeople.

Underpin a building - £17,718

Two storey extension - £88,328

Build a timber frame extension - £26,218

Build a swimming pool - £81,218

Single storey extension - £59,368

Side return extension - £43,957

Install an RSJ - £2,418

Outbuilding - £10,218

Build a Mansard loft conversion - £52,218

Loft conversion - £35,798

Build a kitchen extension - £42,218

Hip to gable loft conversion - £42,218

Granny annexe - £87,218

Garden office - £10,218

Convert a Garage - £16,218

Garage - £18,718

Build a flat roof extension - £22,218

Build a dormer loft conversion - £42,218

Concrete foundations - £6,468

Convert a bungalow loft - £29,218

Convert a basement - £39,957