From £17,476
Grand Homes Developments is an established extension buildering business in SL3. We come highly recommended and provide competitive quotes for your...
From £17,508
Blue Sky Roofing and Home Improvements is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get...
From £17,580
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £17,836
Tom's Builders is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get a competitive quote for...
From £17,564
MRE Maintenance Services is an established and experienced local extension builder in SL3. Please contact us for a free, no obligation quote and co...
From £17,164
I have been in the building trade since I was 14 I've learnt from my father's employees and so on and I know experience is the key to a good job wi...
From £17,644
BDR Home Improvement are here to help customers who need an Extension Builder in SL3. We offer a competitive rate to complete all your extension bu...
From £17,044
Drains R Uss is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get a competitive quote for e...
From £17,308
Relax... you have found a reliable extension builder in SL3. C WINTER BUILDING SERVICES is a friendly and reliable company based in SL3 who conside...
From £17,724
Experienced extension builder ready to quote for your work. My Garage Makeover (UK) is the best extension builder in SL3. No obligation free quotes...

Underpinning ranges from £17,044 (Drains R Uss based in SL3) to £17,836 (Tom's Builders based in SL3), 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 SL3 by posting a job with HaMuch and we will send it to extension builders in SL3.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Slough | £42 | £272 |
| Underpin A Building near Windsor & Maidenhead | £42 | £272 |
| Underpin A Building near Windsor | £41 | £271 |
| Underpin A Building near Staines-upon-Thames | £42 | £269 |
| Underpin A Building near Egham | £42 | £266 |
| Underpin A Building near Hillingdon | £62 | £276 |
| Underpin A Building near Gerrards Cross | £43 | £282 |
| Underpin A Building near Maidenhead | £41 | £273 |
| Underpin A Building near Ascot | £41 | £276 |
| Underpin A Building near Sunbury-on-Thames | £42 | £279 |
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 - £17,485

Two storey extension - £87,977

Build a timber frame extension - £25,985

Build a swimming pool - £80,985

Single storey extension - £54,696

Side return extension - £41,329

Install an RSJ - £2,185

Outbuilding - £9,985

Build a Mansard loft conversion - £51,985

Loft conversion - £33,608

Build a kitchen extension - £41,985

Hip to gable loft conversion - £41,985

Granny annexe - £86,985

Garden office - £9,985

Convert a Garage - £15,985

Garage - £18,485

Build a flat roof extension - £21,985

Build a dormer loft conversion - £41,985

Concrete foundations - £6,235

Convert a bungalow loft - £28,985

Convert a basement - £37,329