From £17,116
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £17,260
Experienced extension builder ready to quote for your work. BHM Leicester is the best extension builder in Northamptonshire. No obligation free quo...
From £17,228
Experienced house builder. Eco structures from Denmark as well as conventional build. Extensions. Bathrooms. Kitchens and support steels when requi...
From £17,244
Trusted and professional extension builder in Northamptonshire. Experienced in all extension buildering work and keeping within budget and on quote...
From £17,076
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £16,972
Northamptonshire, NN17
Ascot Property Solutions Limited is an established and experienced local extension builder in Northamptonshire. Please contact us for a free, no ob...
From £17,100
Northamptonshire, NN6
New Revival - Construction Management is a trusted extension builder serving customers in Northamptonshire and the surrounding area. Contact us to ...
From £17,468
Relax... you have found a reliable extension builder in Northamptonshire. Jogga Construction is a friendly and reliable company based in Northampto...
From £17,556
Kettering Mobile Sandblasting are here to help customers who need an Extension Builder in Northamptonshire. We offer a competitive rate to complete...
From £17,372
I Plowright Brickwork is an established extension buildering business in Northamptonshire. We come highly recommended and provide competitive quote...

Underpinning ranges from £16,972 (Ascot Property Solutions Limited based in NN17) to £17,556 (Kettering Mobile Sandblasting based in NN16), 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 Northamptonshire by posting a job with HaMuch and we will send it to extension builders in Northamptonshire.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Market Harborough | £31 | £217 |
| Underpin A Building near Corby | £30 | £214 |
| Underpin A Building near Kettering | £34 | £237 |
| Underpin A Building near Wigston | £28 | £209 |
| Underpin A Building near Oadby | £28 | £207 |
| Underpin A Building near Hamilton | £29 | £213 |
| Underpin A Building near Leicester | £29 | £213 |
| Underpin A Building near Wellingborough | £39 | £251 |
| Underpin A Building near Northampton | £35 | £239 |
| Underpin A Building near Rugby | £31 | £224 |
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 - £17,239

Two storey extension - £87,609

Build a timber frame extension - £25,739

Build a swimming pool - £80,739

Single storey extension - £49,784

Side return extension - £38,566

Install an RSJ - £1,939

Outbuilding - £9,739

Build a Mansard loft conversion - £51,739

Loft conversion - £31,305

Build a kitchen extension - £41,739

Hip to gable loft conversion - £41,739

Granny annexe - £86,739

Garden office - £9,739

Convert a Garage - £15,739

Garage - £18,239

Build a flat roof extension - £21,739

Build a dormer loft conversion - £41,739

Concrete foundations - £5,989

Convert a bungalow loft - £28,739

Convert a basement - £34,566