Cost to build a flat roof extension in Outer London

Flat roof extension cost in Outer London

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 Outer London?

A flat roof extension ranges from the cheapest of £21,840 (D Postill Builders Ltd based in SE3) to the dearest of £21,944 (Island design & Construction Ltd based in E14), 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 Outer London by posting a job with HaMuch. We'll send it to extension builders in Outer London.

Estimates for flat roof extension near Outer London

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	£17,397
	Build a two storey extension	£87,845
	Build a timber frame extension	£25,897
	Install a swimming pool	£80,897
	Cost to build a single storey extension	£52,933
	Cost to build a side return extension	£40,337
	Install an RSJ	£2,097
	Build an outbuilding	£9,897
	Build a mansard loft conversion	£51,897
	Cost of a loft conversion	£32,781
	Build a kitchen extension	£41,897
	Build a hip to gable loft conversion	£41,897
	Build a granny annexe	£86,897
	Build a garden office	£9,897
	Convert a garage	£15,897
	Build a new garage	£18,397
	Build a flat roof extension	£21,897
	Build a dormer loft conversion	£41,897
	Lay a concrete foundation	£6,147
	Convert a bungalow loft	£28,897
	Basement conversion cost	£36,337

Business name	Flat roof extension cost
Island design & Construction Ltd, Greater London, E14	£21,944
CG Design and Build LTD., London Arena, Greater London, e14	£21,848
CG Design and Build LTD., Greater London, e14	£21,944
ALFA Building Solutions Ltd, London, Greater London, E14	£21,848
ALFA Building Solutions Ltd, Greater London, E14	£21,944
ROOSE CONSTRUCTION LTD, Rotherhithe, SE16	£21,864
MARMAREX, London, Greater London, SE16	£21,848
MARMAREX, London, SE16	£21,944
PHE BUILDING SERVICES, Greater London, E14	£21,944
Trafalgar Building Company Limited, Greenwich, SE10	£21,864
Your Builder Hero, London, E14	£21,944
Prestige Roofing Limited, 70 Colomb Street, Greenwich, London, SE10	£21,896
Storeyboard, London, Greater London, SE10	£21,848
Storeyboard, Greater London, SE10	£21,944
Andy Tunmer Building Services, Canary Wharf, E14	£21,888
WiseContract, Studio 33, Unit 10, elizabeth Industrial Estate, Juno Way, London, Greater London, se14	£21,848
SCL Design & Build Ltd, Londonderry, SE16	£21,944
Team Constructions, Greater London, E14	£21,944
Dumrea Building Construction Ltd, London, SE14	£21,888
AZC BUILDING SERVICES, Greenwich, SE10	£21,864
Cheapest Builder, Rotherhithe, SE16	£21,888
D Postill Builders Ltd, 78 Combe Avenue, London, Greater London, SE3	£21,840
DWL Construction Ltd, London, SE14	£21,944
Builders, Shoreditch, E1	£21,888
Darren & Valentin Construction & Maintenance, Bow, E3	£21,856

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Flat roof extension cost in Outer London

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Flat roof extension cost in Outer London

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