From £52,440
Need to find an Extension Builder near you for all your extension buildering work?
Main Construction provides a local, trusted extension bu...
From £52,008
Whites Carpentry & Building prides in delivering an excellent extension buildering service and value for money in RH20 and the surrounding areas. ...
From £51,872
Need an Extension Builder in RH20? MPS Home Improvements Ltd has been helping local clients (20 mile radius) with their extension buildering jobs f...
From £51,992
Member since August 2026
H P Building Services Sussex is a one-stop solution for all your extension buildering needs. Establish over 10 years ago and covering 20 miles arou...
From £52,168
R S Construction (Surrey) is an established extension buildering business in RH20. We come highly recommended and provide competitive quotes for yo...
From £52,032
We are a family run business we 40 years experience delivering multiple projects from new developments . Extension. Loft conversion. Including foun...
From £52,112
Futureways Design and Build are here to help customers who need an Extension Builder in RH20. We offer a competitive rate to complete all your exte...
From £52,200
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £52,376
Giles Dixon is an experienced Project Manager with over 30 years experience, having worked from the ground up starting in 1984 as an apprentice ele...
From £52,128
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...

Mansard loft conversions range from the cheapest installation of £51,872 (MPS Home Improvements Ltd based in RH14) to the dearest of around £52,440 (Main Construction based in BN12).
While these estimates give you a good idea how much you'll pay for a mansard loft conversion, the only way to get an accurate price is to get real quotes from real builders.
Get quotes to install a mansard loft conversion in RH20 by posting a job with HaMuch and we'll send it to extension builders in RH20.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Build A Mansard Loft Conversion near Rustington | £36 | £246 |
| Build A Mansard Loft Conversion near Littlehampton | £35 | £244 |
| Build A Mansard Loft Conversion near Arun | £35 | £241 |
| Build A Mansard Loft Conversion near Worthing | £35 | £251 |
| Build A Mansard Loft Conversion near Lancing | £37 | £251 |
| Build A Mansard Loft Conversion near Horsham | £38 | £265 |
| Build A Mansard Loft Conversion near Shoreham-by-Sea | £36 | £250 |
| Build A Mansard Loft Conversion near Bognor Regis | £35 | £247 |
| Build A Mansard Loft Conversion near Burgess Hill | £36 | £240 |
| Build A Mansard Loft Conversion near Chichester | £34 | £242 |
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 - £17,633

Two storey extension - £88,199

Build a timber frame extension - £26,133

Build a swimming pool - £81,133

Single storey extension - £57,656

Side return extension - £42,994

Install an RSJ - £2,333

Outbuilding - £10,133

Build a Mansard loft conversion - £52,133

Loft conversion - £34,995

Build a kitchen extension - £42,133

Hip to gable loft conversion - £42,133

Granny annexe - £87,133

Garden office - £10,133

Convert a Garage - £16,133

Garage - £18,633

Build a flat roof extension - £22,133

Build a dormer loft conversion - £42,133

Concrete foundations - £6,383

Convert a bungalow loft - £29,133

Convert a basement - £38,994