From £22,048
Experienced extension builder ready to quote for your work. J&J Building Solutions is the best extension builder in BR7. No obligation free quotes ...
From £22,184
Experienced extension builder ready to quote for your work. CC&D BUILDING LTD is the best extension builder in BR7. No obligation free quotes and m...
From £22,560
Our homes need to be regularly maintained and from time to time they need to be rejuvenated, modernised and enhanced. When it comes to building wor...
From £22,096
Experienced extension builder ready to quote for your work. Mr is the best extension builder in BR7. No obligation free quotes and many happy custo...
From £21,984
JK Doors is a trusted extension builder serving customers in BR7 and the surrounding area. Contact us to today to get a competitive quote for exten...
From £22,192
NIECEIC / NAAPIT GASSAFE WATER REGULATIONS We offer services towards completion of high end construction projects to dis...
From £22,392
Need an Extension Builder in BR7? Samuele Paolini has been helping local clients (5 mile radius) with their extension buildering jobs for many yea...
From £22,312
skilled worker who specializes in completing a wide range of building and renovation projects
From £22,616
HOUSE BUILDING SERVICES LIMITED is a trusted extension builder serving customers in BR7 and the surrounding area. Contact us to today to get a comp...
From £21,888
Member since April 2025
Trusted and professional extension builder in BR7. Experienced in all extension buildering work and keeping within budget and on quote. GR MAINTENA...

A flat roof extension ranges from the cheapest of £21,888 (GR MAINTENANCE LTD based in IG11) to the dearest of £22,616 (HOUSE BUILDING SERVICES LIMITED based in DA16), but these are just estimates. While they give you an idea of who will be better value, the best way to compare costs is to get real quotes.
Find out how much your flat roof extension will cost in BR7 by posting a job with HaMuch. We'll send it to extension builders in BR7.
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 - £17,727

Two storey extension - £88,341

Build a timber frame extension - £26,227

Build a swimming pool - £81,227

Single storey extension - £59,544

Side return extension - £44,056

Install an RSJ - £2,427

Outbuilding - £10,227

Build a Mansard loft conversion - £52,227

Loft conversion - £35,880

Build a kitchen extension - £42,227

Hip to gable loft conversion - £42,227

Granny annexe - £87,227

Garden office - £10,227

Convert a Garage - £16,227

Garage - £18,727

Build a flat roof extension - £22,227

Build a dormer loft conversion - £42,227

Concrete foundations - £6,477

Convert a bungalow loft - £29,227

Convert a basement - £40,056