Convert your basement in SE25 from £32,640

Range from the cheapest Convert a basement £32,640 (Oaksure Construction based in CR0) to the dearest Convert a basement £51,000 (Banga Decoration based in CR7). To see prices and availability for your job click green button.

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From £51,000

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Banga Decoration

Sebastian Banga

Member since August 2025

Banga decoration. Is Base in south London  for number of year  Banga decoration is a small  company. Wich provide an excellent job to the custom...

From £39,120

Last active Nov 26
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Greens Gardening & Landscape Property Maintenance

John Mcdonagh

Watch our short video highlighting all our expertise and services here:

more than 10 y...

From £41,370

Last active Oct 26
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Glenn Miller Builders Limited

Glenn Miller

Relax... you have found a reliable extension builder in SE25. Glenn Miller Builders Limited is a friendly and reliable company based in SE25 who co...

From £40,830

Last active Sep 26
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Aviemore Building Contractors Ltd

Experienced extension builder ready to quote for your work. Aviemore Building Contractors Ltd is the best extension builder in SE25. No obligation ...

From £32,640

Last active Sep 26
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Oaksure Construction

Stuart Bogazzi

Working as a builder for over 20 years now.

Family run business 

Can sort any problem out and help build your dreams.

From £40,380

Last active Sep 26
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Bhagtana & Co Construction

Experienced extension builder ready to quote for your work. Bhagtana & Co Construction is the best extension builder in SE25. No obligation free qu...

From £39,570

Last active Aug 26
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K S BUILDERS (UK) LTD

Trusted and professional extension builder in SE25. Experienced in all extension buildering work and keeping within budget and on quote. K S BUILDE...

From £40,200

Last active Aug 26
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VDL Construction Ltd

Need to find an Extension Builder near you for all your extension buildering work?

VDL Construction Ltd provides a local, trusted extension...

From £38,940

Last active Aug 26
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Top Builders

Experienced extension builder ready to quote for your work. Top Builders is the best extension builder in SE25. No obligation free quotes and many ...

From £41,820

Last active Aug 26
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Howland Building Services

Need to find an Extension Builder near you for all your extension buildering work?

Howland Building Services provides a local, trusted exte...

Cheapest builders to convert your basement in SE25

Estimates for convert a basement near SE25

Comparing extension builders estimates for a Convert a basement gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.

What to do - Get rates and quotes for the cost to convert a basement in SE25 by posting a job with HaMuch and we will send it to  extension builders in SE25.

"Basement conversion" - BECKENHAM, job posted 01/01/70


Estimates for common extension builder jobs in SE25;

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.

More extensions & conversions cost guides...