Cost to build a flat roof extension in SW1

Flat roof extension cost in SW1

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 SW1?

A flat roof extension ranges from the cheapest of £20,160 (London Design And Build based in SW1A) to the dearest of £21,944 (ALT CONSTRUCTION based in SW1W), 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 SW1 by posting a job with HaMuch. We'll send it to extension builders in SW1.

Estimates for flat roof extension near SW1

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	£17,319
	Build a two storey extension	£87,728
	Build a timber frame extension	£25,819
	Install a swimming pool	£80,819
	Cost to build a single storey extension	£51,371
	Cost to build a side return extension	£39,459
	Install an RSJ	£2,019
	Build an outbuilding	£9,819
	Build a mansard loft conversion	£51,819
	Cost of a loft conversion	£32,049
	Build a kitchen extension	£41,819
	Build a hip to gable loft conversion	£41,819
	Build a granny annexe	£86,819
	Build a garden office	£9,819
	Convert a garage	£15,819
	Build a new garage	£18,319
	Build a flat roof extension	£21,819
	Build a dormer loft conversion	£41,819
	Lay a concrete foundation	£6,069
	Convert a bungalow loft	£28,819
	Basement conversion cost	£35,459

Business name	Flat roof extension cost
A to Z Builders Ltd, Houses of Parliament, SW1P	£21,880
F & F Building Services, Houses of Parliament, SW1P	£21,880
London Design And Build , Roehampton, SW1A	£20,160
London Projects Ltd, 11 Carteret Street, London, Greater London, SW1H	£21,848
Luxury Movement, London, Greater London, SW1V	£21,840
Cliden Construction (London), London, Greater London, SW1V	£21,840
Future Homes Design and Build, 4 Old Park Lane, Mayfair, London, W1K	£21,848
ALT CONSTRUCTION, Greater London, SW1W	£21,944
The Maybria Group, Mayfair, Greater London, W1J	£21,848
Property Refurbishment London, 21 Ellis Street, Sloane Square, London, Greater London, SW1X	£21,840
Mayfair Design, Greater London, W1J	£21,944
Sloane Ave Renovations, 130 Sloane Street, London, Greater London, SW1X	£21,840
Knightsbridge Design, Greater London, SW1X	£21,944
Autas Developments, London, SW1W	£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
Elv8 Interiors, Greater London, W1B	£21,944
Adamko Dry Lining London, Greater London, WC2N	£21,944
Hearne House, London, Greater London, SW3	£21,840
Cobalt Interiors, London, Greater London, SW7	£21,944
Pillar Contractors Ltd, 49 Grosvenor Street, Mayfair, London, Greater London, W1K	£21,840
Clarisford, London, Greater London, SW3	£21,840
Clarisford, Greater London, SW3	£21,944
Big Mamma, Greater London, W1F	£21,944

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Flat roof extension cost in SW1

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Flat roof extension cost in SW1

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