Cost to build a flat roof extension in Barnes

Flat roof extension cost in Barnes

A flat roof extension is a great way to add extra space to your home without splashing out on the costs of a pitched roof extension. Often exempt from planning permission rules, you can build a flat roof extension up to 3 metres in height as long as it's not visible from a road. But how much do they cost in Barnes?

A flat roof extension ranges from the cheapest of £21,840 (London House Companies Ltd based in SW13) to the dearest of £21,944 (Build & Designs Ltd based in SW13), 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 Barnes by posting a job with HaMuch. We'll send it to extension builders in Barnes.

Estimates for flat roof extension near Barnes

"Flat roof extension for a period mews terraced house. We'd like a bedroom extension with full bathroom and a roof top terrace. Footprint is roughly 8.5m x 6m."

How much does a flat roof extension cost?
Flat roof extension cost per m2
Factors affecting the cost of flat roof extensions
Advantages and disadvantages of flat roofs
Which is cheaper: a flat roof or pitched roof?
How long does a flat roof extension take?
Do you need planning permission for a flat roof extension?
How long does a flat roof last?
Can you walk on a flat roof extension?
What insulation do I need for a flat roof extension?

	Job	Estimate
	Underpinning a house	£17,379
	Build a two storey extension	£87,819
	Build a timber frame extension	£25,879
	Install a swimming pool	£80,879
	Cost to build a single storey extension	£52,581
	Cost to build a side return extension	£40,139
	Install an RSJ	£2,079
	Build an outbuilding	£9,879
	Build a mansard loft conversion	£51,879
	Cost of a loft conversion	£32,616
	Build a kitchen extension	£41,879
	Build a hip to gable loft conversion	£41,879
	Build a granny annexe	£86,879
	Build a garden office	£9,879
	Convert a garage	£15,879
	Build a new garage	£18,379
	Build a flat roof extension	£21,879
	Build a dormer loft conversion	£41,879
	Lay a concrete foundation	£6,129
	Convert a bungalow loft	£28,879
	Basement conversion cost	£36,139

Business name	Flat roof extension cost
London House Companies Ltd, London, Greater London, SW13	£21,840
Invicta Construction LTD, 10-12 Barnes High Street, Barnes,, London, London, Greater London, SW13	£21,840
True Linear, london, sw13	£21,888
Big Bean Construction ltd, London, Greater London, SW13	£21,840
Build & Designs Ltd, London, SW13	£21,944
Design 2 Finish, London, Greater London, SW13	£21,840
Convert Construction Ltd, London, Greater London, SW14	£21,840
WBS Refurbishments and Renovations LTD, London, Greater London, SW15	£21,840
GP Basement Building & Refurbishment, London, Greater London, sw15	£21,840
Smart Property Sourcing, Midlothian, W4	£21,944
Raylian Power Design, Greater London, SW14	£21,944
Raylian Power Design, 206 Mortlake Business Centre, 20 Mortlake High Street, Mortlake, Greater London, SW14	£21,840
MCB Developments, London, Greater London, SW14	£21,840
AJ Wells, Putney, SW15	£21,880
Metos Design & Build, Surrey, SW14	£21,944
Specialist Screeding, Hammersmith, W6	£21,888
Knight Refurbishment House Renovation, Greater London, W4	£21,944
Sunny Eco, 345 Upper Richmond Road, London, Surrey, SW14	£21,840
Ethos Urban Design, London, Greater London, SW15	£21,840
Build Space London Ltd, London, Greater London, SW14	£21,840
JOHN HOPWOOD DELTA CONSTRUCTION SERVICES, Chiswick, W4	£21,848
Lux Construction, Hammersmith, Greater London, W6	£21,848
Gem Look Construction Ltd., Richmond Surrey, SW14	£21,936
Guardian Developments, Londonderry, W4	£21,944
Hurlingham Developments, Greater London, SW6	£21,944

Extend your Barnes with an extension

Flat roof extension cost in Barnes

Estimates for common extension builder jobs in Barnes;

Rates for other Barnes trades

Flat roof extension cost in Barnes

Get extension builder rates instantly