Cost to build a flat roof extension in W1J

Flat roof extension cost in W1J

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 W1J?

A flat roof extension ranges from the cheapest of £20,160 (London Design And Build based in SW1A) to the dearest of £21,944 (Mayfair Design based in W1J), 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 W1J by posting a job with HaMuch. We'll send it to extension builders in W1J.

Estimates for flat roof extension near W1J

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	£17,335
	Build a two storey extension	£87,752
	Build a timber frame extension	£25,835
	Install a swimming pool	£80,835
	Cost to build a single storey extension	£51,698
	Cost to build a side return extension	£39,642
	Install an RSJ	£2,035
	Build an outbuilding	£9,835
	Build a mansard loft conversion	£51,835
	Cost of a loft conversion	£32,202
	Build a kitchen extension	£41,835
	Build a hip to gable loft conversion	£41,835
	Build a granny annexe	£86,835
	Build a garden office	£9,835
	Convert a garage	£15,835
	Build a new garage	£18,335
	Build a flat roof extension	£21,835
	Build a dormer loft conversion	£41,835
	Lay a concrete foundation	£6,085
	Convert a bungalow loft	£28,835
	Basement conversion cost	£35,642

Business name	Flat roof extension cost
Mayfair Design, Greater London, W1J	£21,944
Luxe Refurbs, 16 Berkeley Street, London, Greater London, W1J	£21,840
We Love Build - Three Arches, London, Greater London, W1J	£21,840
We Love Build, Greater London, W1J	£21,944
The Maybria Group, Mayfair, Greater London, W1J	£21,848
Future Homes Design and Build, 4 Old Park Lane, Mayfair, London, W1K	£21,848
Elv8 Interiors, Greater London, W1B	£21,944
Pillar Contractors Ltd, 49 Grosvenor Street, Mayfair, London, Greater London, W1K	£21,840
Starfish Properties, 14 Hanover Street, 3rd Floor, London, W1S	£21,848
London Design And Build , Roehampton, SW1A	£20,160
Dominic Payte - Design & Build, 14 Hanover Square, Mayfair, Greater London, W1S	£21,848
Big Mamma, Greater London, W1F	£21,944
Cornerstone, Greater London, W1F	£21,944
Sehem Design, london, W1F	£21,944
London Projects Ltd, 11 Carteret Street, London, Greater London, SW1H	£21,848
CORRECTBUILDIV.LTD, Greater London, W1B	£21,944
Hestia Contractors Ltd, 207 Regent Street, London, Greater London, W1B	£21,848
Guildon LTD, Greater London, w1b	£21,944
Azur London, Greater London, W1U	£21,944
KBB Master Builder LTD, Greater London, W1W	£21,944
UCS UK Ltd, Greater London, W1W	£21,944
Eternal Solutions, Greater London, W1W	£21,944
JK Doors, Fitzrovia, W1W	£21,888
KBB Master Builder Ltd, Greater London, W1W	£21,944
JAY Executinos LTD, London, W1W	£21,944

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Flat roof extension cost in W1J

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Flat roof extension cost in W1J

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