Cost to build a flat roof extension in SW12

Flat roof extension cost in SW12

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 SW12?

A flat roof extension ranges from the cheapest of £21,840 (Orchestrate based in SW11) to the dearest of £22,000 (JT Allen based in SW17), 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 SW12 by posting a job with HaMuch. We'll send it to extension builders in SW12.

Estimates for flat roof extension near SW12

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	£17,389
	Build a two storey extension	£87,833
	Build a timber frame extension	£25,889
	Install a swimming pool	£80,889
	Cost to build a single storey extension	£52,773
	Cost to build a side return extension	£40,247
	Install an RSJ	£2,089
	Build an outbuilding	£9,889
	Build a mansard loft conversion	£51,889
	Cost of a loft conversion	£32,706
	Build a kitchen extension	£41,889
	Build a hip to gable loft conversion	£41,889
	Build a granny annexe	£86,889
	Build a garden office	£9,889
	Convert a garage	£15,889
	Build a new garage	£18,389
	Build a flat roof extension	£21,889
	Build a dormer loft conversion	£41,889
	Lay a concrete foundation	£6,139
	Convert a bungalow loft	£28,889
	Basement conversion cost	£36,247

Business name	Flat roof extension cost
Barnard Interiors, London, Greater London, SW12	£21,944
IDL Contractors Ltd, London, Greater London, SW12	£21,848
M. Watkins and Sons Ltd, Greater London, SW12	£21,944
R C BUILDER, Balham, SW12	£21,864
Zenico, 53 Carminia Road, London, Greater London, SW17	£21,848
Interior Space Solutions Ltd, Surrey, SW12	£21,944
Basenet Ltd, London, SW4	£21,944
Hughes Developments, London, Greater London, SW17	£21,848
William Coles, London, Surrey, SW16	£21,848
RenoView Ltd, Greater London, SW16	£21,944
JT Allen, Rettendon, Chelmsford, SW17	£22,000
Apartment Renovation Limited, 197 Macmillan Way, London, Greater London, sw17	£21,848
Studio Such, Greater London, SW16	£21,944
Build and Convert Services, 10 Streatleigh Parade, Streatham High Road, London, Greater London, SW16	£21,848
Orchestrate, 53 Webb's Road, London, Greater London, SW11	£21,840
All Trades Builders, Brixton, SW2	£21,864
Grosvenor House Construction Ltd., 112A Clapham Park Road, London, London, Greater London, sw4	£21,848
Nova Renovation, Nova, London, SW16	£21,848
Damian Szlema Construction LTD, Leigham Avenue, Lond, SW16	£21,864
M PIETROW T/A M P BUILDERS, Brixton, SW2	£21,864
Paddy Brown, 67 Wingate Square, Clapham, London, Greater London, SW4	£21,848
South London Conversions Ltd, London, SW4	£21,888
Grandiem Vero, Greater London, SW4	£21,944
Hawksmoor Construction, Clapham Common, SW4	£21,944
PEAKE Projects London Ltd, London, Greater London, SW16	£21,848

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Flat roof extension cost in SW12

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Flat roof extension cost in SW12

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