From £17,940
Need to find an Extension Builder near you for all your extension buildering work?
Main Construction provides a local, trusted extension bu...
From £17,508
Whites Carpentry & Building prides in delivering an excellent extension buildering service and value for money in Storrington and the surrounding a...
From £17,372
Need an Extension Builder in Storrington? MPS Home Improvements Ltd has been helping local clients (20 mile radius) with their extension buildering...
From £17,492
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 £17,668
R S Construction (Surrey) is an established extension buildering business in Storrington. We come highly recommended and provide competitive quotes...
From £17,532
We are a family run business we 40 years experience delivering multiple projects from new developments . Extension. Loft conversion. Including foun...
From £17,612
Futureways Design and Build are here to help customers who need an Extension Builder in Storrington. We offer a competitive rate to complete all yo...
From £17,700
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £17,876
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 £17,628
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...

Underpinning ranges from £17,372 (MPS Home Improvements Ltd based in RH14) to £17,940 (Main Construction based in BN12), but the final cost will depend on the method of underpinning used, how much of your foundations need underpinning and where you live.
Comparing extension builders estimates for underpinning gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
Get quotes to underpin your home in Storrington by posting a job with HaMuch and we will send it to extension builders in Storrington.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Rustington | £36 | £246 |
| Underpin A Building near Littlehampton | £35 | £244 |
| Underpin A Building near Arun | £35 | £241 |
| Underpin A Building near Worthing | £35 | £251 |
| Underpin A Building near Lancing | £37 | £251 |
| Underpin A Building near Horsham | £38 | £265 |
| Underpin A Building near Shoreham-by-Sea | £36 | £250 |
| Underpin A Building near Bognor Regis | £35 | £247 |
| Underpin A Building near Burgess Hill | £36 | £240 |
| Underpin A Building 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