From £22,096
Omniform are here to help customers who need an Extension Builder in Mansion House. We offer a competitive rate to complete all your extension buil...
From £22,288
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,256
Need an Extension Builder in Mansion House? Flow Property Services has been helping local clients (5 mile radius) with their extension buildering j...
From £22,272
Need an Extension Builder in Mansion House? Aylaa Exclusive has been helping local clients (5 mile radius) with their extension buildering jobs for...
From £22,392
We have the experience and knowledge to carry out any project, big or small. Our team of experts thoroughly plan the budget and manage your projec...
From £22,408
London Roof Gardens is a trusted extension builder serving customers in Mansion House and the surrounding area. Contact us to today to get a compet...
From £21,992
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £22,104
SCANDIIN is an established and experienced local extension builder in Mansion House. Please contact us for a free, no obligation quote and competit...
From £22,472
Need an Extension Builder in Mansion House? GenUp Digital has been helping local clients (5 mile radius) with their extension buildering jobs for m...
From £22,160
Venta Construction is an established and experienced local extension builder in Mansion House. Please contact us for a free, no obligation quote an...

A flat roof extension ranges from the cheapest of £21,992 (SDL PKB based in Ec4a) to the dearest of £22,472 (GenUp Digital based in EC3M), 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 Mansion House by posting a job with HaMuch. We'll send it to extension builders in Mansion House.
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 - £17,744

Two storey extension - £88,366

Build a timber frame extension - £26,244

Build a swimming pool - £81,244

Single storey extension - £59,880

Side return extension - £44,245

Install an RSJ - £2,444

Outbuilding - £10,244

Build a Mansard loft conversion - £52,244

Loft conversion - £36,038

Build a kitchen extension - £42,244

Hip to gable loft conversion - £42,244

Granny annexe - £87,244

Garden office - £10,244

Convert a Garage - £16,244

Garage - £18,744

Build a flat roof extension - £22,244

Build a dormer loft conversion - £42,244

Concrete foundations - £6,494

Convert a bungalow loft - £29,244

Convert a basement - £40,245