From £17,844
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £17,812
Orpington, BR6
Trusted and professional extension builder in Orpington. Experienced in all extension buildering work and keeping within budget and on quote. ORBIT...
From £18,028
Our building services company AL-KO Renovations was established over 12 years ago. Since then we have been helping customers in the area by providi...
From £17,508
LBS Builders is an established and experienced local extension builder in Orpington. Please contact us for a free, no obligation quote and competit...
From £17,716
Relax... you have found a reliable extension builder in Orpington. POVERSET BUILDING COMPANY is a friendly and reliable company based in Orpington ...
From £17,580
Need an Extension Builder in Orpington? Cygnus Construction has been helping local clients (10 mile radius) with their extension buildering jobs fo...
From £17,596
Need an Extension Builder in Orpington? P&k Building Ltd has been helping local clients (10 mile radius) with their extension buildering jobs for m...
From £17,396
MONUMENTAL CONSTRUCTION LIMITE are here to help customers who need an Extension Builder in Orpington. We offer a competitive rate to complete all y...
From £17,580
Experienced extension builder ready to quote for your work. Probuilder London Ltd is the best extension builder in Orpington. No obligation free qu...
From £17,692
Oakmore Builders Limited is a trusted extension builder serving customers in Orpington and the surrounding area. Contact us to today to get a compe...

Underpinning ranges from £17,396 (MONUMENTAL CONSTRUCTION LIMITE based in BR2) to £18,028 (AL-KO Construction Ltd based in BR5), 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 Orpington by posting a job with HaMuch and we will send it to extension builders in Orpington.
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 - £17,675

Two storey extension - £88,263

Build a timber frame extension - £26,175

Build a swimming pool - £81,175

Single storey extension - £58,504

Side return extension - £43,471

Install an RSJ - £2,375

Outbuilding - £10,175

Build a Mansard loft conversion - £52,175

Loft conversion - £35,393

Build a kitchen extension - £42,175

Hip to gable loft conversion - £42,175

Granny annexe - £87,175

Garden office - £10,175

Convert a Garage - £16,175

Garage - £18,675

Build a flat roof extension - £22,175

Build a dormer loft conversion - £42,175

Concrete foundations - £6,425

Convert a bungalow loft - £29,175

Convert a basement - £39,471