Cost to build a flat roof extension in Chiswick

Flat roof extension cost in Chiswick

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 Chiswick?

A flat roof extension ranges from the cheapest of £21,832 (Starling Constructions Ltd based in W4) to the dearest of £22,800 (Adrian Design Ltd based in W4), 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 Chiswick by posting a job with HaMuch. We'll send it to extension builders in Chiswick.

Estimates for flat roof extension near Chiswick

"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	£17,431
	Build a two storey extension	£87,896
	Build a timber frame extension	£25,931
	Install a swimming pool	£80,931
	Cost to build a single storey extension	£53,618
	Cost to build a side return extension	£40,722
	Install an RSJ	£2,131
	Build an outbuilding	£9,931
	Build a mansard loft conversion	£51,931
	Cost of a loft conversion	£33,102
	Build a kitchen extension	£41,931
	Build a hip to gable loft conversion	£41,931
	Build a granny annexe	£86,931
	Build a garden office	£9,931
	Convert a garage	£15,931
	Build a new garage	£18,431
	Build a flat roof extension	£21,931
	Build a dormer loft conversion	£41,931
	Lay a concrete foundation	£6,181
	Convert a bungalow loft	£28,931
	Basement conversion cost	£36,722

Business name	Flat roof extension cost
Starling Constructions Ltd, London, W4	£21,832
SxS Design & Build, Greater London, W4	£21,944
Kuta Design and Build Limited, Greater London, W4	£21,944
Arrow Design LTD, London, Londonderry, W4	£21,840
ASSEGAI DESIGN&BUILD, Chiswick, W4	£21,864
Elite London Construction, 9 Fisher's Lane, Chiswick, London, Greater London, W4	£21,840
Good Design and Build, London, Greater London, W4	£21,840
Guardian Developments, Londonderry, W4	£21,944
Zulufish, 26 Arlington Gardens, Chiswick, London, Greater London, W4	£21,840
Smart Property Sourcing, Midlothian, W4	£21,944
Pipedreams Interiors Ltd, 33c Saville Road, Chiswick, London, Greater London, W4	£21,944
Adrian Design Ltd, Chiswick , W4	£22,800
R Burton & Sons Builders, Chiswick, W4	£21,864
SW CHELSEA CONSTRUCTION, Greater London, W4	£21,944
Magill Travill Construction, Chiswick, W4	£21,888
Knight Refurbishment House Renovation, Greater London, W4	£21,944
P and J Roofing & Building Contractors Ltd, 35 Colville Road, London, Greater London, W3	£21,944
Specialist Screeding, Hammersmith, W6	£21,888
Hamilton King, Greater London, W4	£21,840
Raremade, Greater London, W3	£21,944
JOHN HOPWOOD DELTA CONSTRUCTION SERVICES, Chiswick, W4	£21,848
Shape Design & Build, Sun Studios, 30 Warple Way, London, Greater London, W3	£21,840
Nomex Design, Greater London, w3	£21,944
C H Westend, 380 Bollo Lane, London, Greater London, W3	£21,944
CHISWICK CONSTRUCTION LTD, Acton, W3	£21,864

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Flat roof extension cost in Chiswick

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Flat roof extension cost in Chiswick

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