From £21,936
Extensions, Refurbishments & Loft ConversionsAt Keystone our mission is to help our clients imagine, design & build environments that enhance their...
From £21,808
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,112
Experienced extension builder ready to quote for your work. MRA CONSTRUCTION is the best extension builder in RH16. No obligation free quotes and m...
From £22,008
Need to find an Extension Builder near you for all your extension buildering work?
Tj's Fencing provides a local, trusted extension builder...
From £22,600
Rjscarpentryconstruction is a well established company with over 30 years of experience in the carpentry and construction industries
From £21,848
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,360
TOLLEY CARPENTRY is an established extension buildering business in RH16. We come highly recommended and provide competitive quotes for your work.<...
From £22,064
JG Brickwork Services Limited is an established extension buildering business in RH16. We come highly recommended and provide competitive quotes fo...
From £21,736
Relax... you have found a reliable extension builder in RH16. Atlas Installations is a friendly and reliable company based in RH16 who consider no ...
From £21,784
In an unstable market house extensions are often the most viable option, helping you to get the most out of the space you have without the addition...

A flat roof extension ranges from the cheapest of £21,736 (Atlas Installations based in RH15) to the dearest of £22,600 (RJ's Carpentry Construction based in RH15), 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 RH16 by posting a job with HaMuch. We'll send it to extension builders in RH16.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Build A Flat Roof Extension near Haywards Heath | £35 | £256 |
| Build A Flat Roof Extension near Mid Sussex | £35 | £261 |
| Build A Flat Roof Extension near Burgess Hill | £36 | £240 |
| Build A Flat Roof Extension near Crawley | £38 | £255 |
| Build A Flat Roof Extension near East Grinstead | £37 | £259 |
| Build A Flat Roof Extension near Horsham | £38 | £265 |
| Build A Flat Roof Extension near Brighton and Hove | £35 | £251 |
| Build A Flat Roof Extension near Horley | £38 | £258 |
| Build A Flat Roof Extension near Crowborough | £36 | £258 |
| Build A Flat Roof Extension near Brighton | £35 | £251 |
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 - £17,526

Two storey extension - £88,038

Build a timber frame extension - £26,026

Build a swimming pool - £81,026

Single storey extension - £55,512

Side return extension - £41,788

Install an RSJ - £2,226

Outbuilding - £10,026

Build a Mansard loft conversion - £52,026

Loft conversion - £33,990

Build a kitchen extension - £42,026

Hip to gable loft conversion - £42,026

Granny annexe - £87,026

Garden office - £10,026

Convert a Garage - £16,026

Garage - £18,526

Build a flat roof extension - £22,026

Build a dormer loft conversion - £42,026

Concrete foundations - £6,276

Convert a bungalow loft - £29,026

Convert a basement - £37,788