D C Salsbury Builders is an established and experienced local extension builder in CM23. Please contact us for a free, no obligation quote and comp...
Need to find an Extension Builder near you for all your extension buildering work?
JKL Construction & Carpentry Ltd provides a local, trust...
Dan Nevill
Nevill Design & Build specialises in high-quality house extensions, loft conversions, structural alterations, and full refurbishments. We’ve deli...
From £20,864
Valy
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,440
Linear Carpentry and Building has been helping customers in Hertfordshire and the surrounding area by providing professional and trustworthy buildi...
From £22,472
Wade developments are here to help customers who need an Extension Builder in CM23. We offer a competitive rate to complete all your extension buil...
From £22,216
Need an Extension Builder in CM23? Stewart & Sons Ltd. has been helping local clients (20 mile radius) with their extension buildering jobs for man...
From £22,224
Trusted and professional extension builder in CM23. Experienced in all extension buildering work and keeping within budget and on quote. Ratcliff &...

A flat roof extension ranges from the cheapest of £20,864 (V S M Property Services Ltd based in CM23) to the dearest of £22,472 (Wade developments based in Cm23), 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 CM23 by posting a job with HaMuch. We'll send it to extension builders in CM23.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Build A Flat Roof Extension near Bishop's Stortford | £42 | £264 |
| Build A Flat Roof Extension near Harlow | £43 | £288 |
| Build A Flat Roof Extension near Ware | £47 | £296 |
| Build A Flat Roof Extension near East Hertfordshire | £44 | £289 |
| Build A Flat Roof Extension near Hoddesdon | £46 | £296 |
| Build A Flat Roof Extension near Hertford | £46 | £290 |
| Build A Flat Roof Extension near Cheshunt | £48 | £285 |
| Build A Flat Roof Extension near Stevenage | £44 | £282 |
| Build A Flat Roof Extension near Welwyn Garden City | £42 | £269 |
| Build A Flat Roof Extension near Epping Forest | £44 | £274 |
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 - £17,599

Two storey extension - £88,149

Build a timber frame extension - £26,099

Build a swimming pool - £81,099

Single storey extension - £56,980

Side return extension - £42,614

Install an RSJ - £2,299

Outbuilding - £10,099

Build a Mansard loft conversion - £52,099

Loft conversion - £34,678

Build a kitchen extension - £42,099

Hip to gable loft conversion - £42,099

Granny annexe - £87,099

Garden office - £10,099

Convert a Garage - £16,099

Garage - £18,599

Build a flat roof extension - £22,099

Build a dormer loft conversion - £42,099

Concrete foundations - £6,349

Convert a bungalow loft - £29,099

Convert a basement - £38,614