From £21,800
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,152
Prestige Build Services LTD is a trusted extension builder serving customers in SN1 and the surrounding area. Contact us to today to get a competit...
From £21,536
Need an Extension Builder in SN1? R PEARCE BUILDING has been helping local clients (20 mile radius) with their extension buildering jobs for many y...
From £22,096
MJ solutions is an established and experienced local extension builder in SN1. Please contact us for a free, no obligation quote and competitive r...
From £22,128
Relax... you have found a reliable extension builder in SN1. CHF CONSTRUCTION is a friendly and reliable company based in SN1 who consider no job a...
From £22,056
DSA CONSTRUCTION is an established extension buildering business in SN1. We come highly recommended and provide competitive quotes for your work.
From £21,864
Relax... you have found a reliable extension builder in SN1. A P BUILDING CONTRACTORS LTD is a friendly and reliable company based in SN1 who consi...
From £21,480
MR HOWELL are here to help customers who need an Extension Builder in SN1. We offer a competitive rate to complete all your extension buildering jo...
From £22,152
Need to find an Extension Builder near you for all your extension buildering work?
A S A BUILDING SERVICES LTD provides a local, trusted ex...
From £21,952
A D BUILDING SERVICES T/A is a trusted extension builder serving customers in SN1 and the surrounding area. Contact us to today to get a competitiv...

A flat roof extension ranges from the cheapest of £21,480 (MR HOWELL based in SN3) to the dearest of £22,152 (Prestige Build Services LTD based in SN5), 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 SN1 by posting a job with HaMuch. We'll send it to extension builders in SN1.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Build A Flat Roof Extension near Swindon | £38 | £238 |
| Build A Flat Roof Extension near Stratton St Margaret | £37 | £238 |
| Build A Flat Roof Extension near Thamesdown | £38 | £239 |
| Build A Flat Roof Extension near Calne | £29 | £225 |
| Build A Flat Roof Extension near Vale of White Horse | £36 | £271 |
| Build A Flat Roof Extension near North Wiltshire | £32 | £242 |
| Build A Flat Roof Extension near West Wiltshire | £32 | £242 |
| Build A Flat Roof Extension near Devizes | £32 | £242 |
| Build A Flat Roof Extension near Chippenham | £34 | £258 |
| Build A Flat Roof Extension near Witney | £32 | £244 |
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 - £17,422

Two storey extension - £87,882

Build a timber frame extension - £25,922

Build a swimming pool - £80,922

Single storey extension - £53,432

Side return extension - £40,618

Install an RSJ - £2,122

Outbuilding - £9,922

Build a Mansard loft conversion - £51,922

Loft conversion - £33,015

Build a kitchen extension - £41,922

Hip to gable loft conversion - £41,922

Granny annexe - £86,922

Garden office - £9,922

Convert a Garage - £15,922

Garage - £18,422

Build a flat roof extension - £21,922

Build a dormer loft conversion - £41,922

Concrete foundations - £6,172

Convert a bungalow loft - £28,922

Convert a basement - £36,618