From £17,228
ATJ BUILDING & GROUNDWORKS is a trusted extension builder serving customers in NN5 and the surrounding area. Contact us to today to get a competiti...
From £17,484
Need to find an Extension Builder near you for all your extension buildering work?
Picking your Local Builder provides a local, trusted ext...
From £17,692
Relax... you have found a reliable extension builder in NN5. Wright Building is a friendly and reliable company based in NN5 who consider no job as...
From £16,908
We have a great team behind us, we offer friendly, competitive and professional service. With years of experience among the trades, there's not muc...
From £17,436
L.D.Design&Build means a holistic approach to building, one simple way of finding everything you need for your building project under the ‘same r...
From £17,612
Need to find an Extension Builder near you for all your extension buildering work?
The Builders - Northampton Limited provides a local, tru...
From £17,364
Walsh Builders Ltd is an established and experienced local extension builder in NN5. Please contact us for a free, no obligation quote and competit...
From £17,116
Brickwork specialist with 30 years experience.
From repointing, small repairs up to building extensions and houses.
Stonework...
From £17,100
M Home Renovations is an established extension buildering business in NN5. We come highly recommended and provide competitive quotes for your work....
From £17,372
Need an Extension Builder in NN5? DAB & K&G Building Services has been helping local clients (20 mile radius) with their extension buildering jobs ...

Underpinning ranges from £16,908 (Artizan Roofing based in NN2) to £17,692 (Wright Building based in NN4), 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 NN5 by posting a job with HaMuch and we will send it to extension builders in NN5.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Northampton | £35 | £240 |
| Underpin A Building near Wellingborough | £39 | £251 |
| Underpin A Building near Daventry | £31 | £230 |
| Underpin A Building near Kettering | £34 | £237 |
| Underpin A Building near Rushden | £34 | £231 |
| Underpin A Building near Milton Keynes | £39 | £263 |
| Underpin A Building near Market Harborough | £31 | £217 |
| Underpin A Building near Rugby | £31 | £224 |
| Underpin A Building near Bletchley | £39 | £265 |
| Underpin A Building near Corby | £30 | £214 |
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 - £17,331

Two storey extension - £87,747

Build a timber frame extension - £25,831

Build a swimming pool - £80,831

Single storey extension - £51,624

Side return extension - £39,601

Install an RSJ - £2,031

Outbuilding - £9,831

Build a Mansard loft conversion - £51,831

Loft conversion - £32,168

Build a kitchen extension - £41,831

Hip to gable loft conversion - £41,831

Granny annexe - £86,831

Garden office - £9,831

Convert a Garage - £15,831

Garage - £18,331

Build a flat roof extension - £21,831

Build a dormer loft conversion - £41,831

Concrete foundations - £6,081

Convert a bungalow loft - £28,831

Convert a basement - £35,601