Experienced extension builder ready to quote for your work. Grant Construction is the best extension builder in SO51. No obligation free quotes and...
The business offers a full design service for both kitchens and bathrooms.We work with you to make the best use of your space and find prod...
From £16,788
James Golby
All our work carries a life time guarantee , If we did it and you have a problem we want to know about it. Not the bloke in the pub or your next do...
From £17,772
Ibcon Construction is an established and experienced local extension builder in SO51. Please contact us for a free, no obligation quote and competi...
From £17,412
BUY BUILDER LTD is an established extension buildering business in SO51. We come highly recommended and provide competitive quotes for your work.
From £17,460
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £17,404
Our building services company KT Carpentry & Building Services has been helping customers in Southampton, Winchester, Brockenhurst and Portsmouth b...
From £17,564
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...

Underpinning ranges from £16,788 (James Golby Construction based in SO51) to £17,772 (Ibcon Construction based in SO51), 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 SO51 by posting a job with HaMuch and we will send it to extension builders in SO51.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Romsey | £32 | £230 |
| Underpin A Building near Chandler's Ford | £34 | £245 |
| Underpin A Building near Totton | £34 | £243 |
| Underpin A Building near Eastleigh | £34 | £244 |
| Underpin A Building near Southampton | £34 | £243 |
| Underpin A Building near Test Valley | £37 | £261 |
| Underpin A Building near New Forest | £32 | £245 |
| Underpin A Building near Winchester | £39 | £283 |
| Underpin A Building near Hedge End | £34 | £244 |
| Underpin A Building near Locks Heath | £33 | £240 |
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 - £17,453

Two storey extension - £87,930

Build a timber frame extension - £25,953

Build a swimming pool - £80,953

Single storey extension - £54,060

Side return extension - £40,971

Install an RSJ - £2,153

Outbuilding - £9,953

Build a Mansard loft conversion - £51,953

Loft conversion - £33,309

Build a kitchen extension - £41,953

Hip to gable loft conversion - £41,953

Granny annexe - £86,953

Garden office - £9,953

Convert a Garage - £15,953

Garage - £18,453

Build a flat roof extension - £21,953

Build a dormer loft conversion - £41,953

Concrete foundations - £6,203

Convert a bungalow loft - £28,953

Convert a basement - £36,971