Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.65 (20 reviews)

Find affordable BN1 extension builders

Extension builders rates in BN1 range from £31/hour £221/day (Graeme Davies Plumbing and Heating) to £49/hour £390/day (CITY BUILDING SERVICES LIMITED). To see prices and availability now for your job click Get quotes.

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"KITCHEN EXTENSION BRIGHTON" - BN2, job posted 08/10/26

"Loft conversion" - BN1, job posted 05/09/26

"Cost to build a side return extension" - BN2, job posted 30/03/26

"Single storey extension" - BN42, job posted 06/01/26

"Build ground floor single story extension. 3m permitted development, house is 7.5m wide. Assume 4x velux in pitched roof" - BN1, job posted 30/09/25

"Single storey extension" - BRIGHTON AND HOVE, job posted 30/09/25

"Side return extension" - BRIGHTON, job posted 30/08/25

"Single storey extension" - HOVE, job posted 27/08/25

"Mansard loft conversion" - BRIGHTON AND HOVE, job posted 22/08/25

"Https://www.rightmove.co.uk/properties/1583 6xxx #/?channel=RES_BUY Can you give us a quote for excavation and conversion of this basement based on what you can see in this rightmove advert?" - BRIGHTON, job posted 04/08/25

"Kitchen extension" - HOVE, job posted 03/08/25

"Side return extension" - BRIGHTON, job posted 22/07/25

"Underpinning" - BRIGHTON, job posted 21/07/25

"Two storey extension" - BN88, job posted 19/05/25

"Single storey extension" - HOVE, job posted 06/05/25

"Convert a bungalow loft" - BN1, job posted 23/04/25

"Side return extension" - BRIGHTON, job posted 19/04/25

"Loft conversion" - HOVE, job posted 05/04/25

"Side return extension" - BRIGHTON, job posted 01/04/25

"Side return extension" - BRIGHTON, job posted 25/02/25

What are the best ways to avoid problems when paying the Extension Builder?

The most important thing is do avoid handing over cash or paying large sums in advance. Be wary of paying cash for a cheaper job, i.e. to avoid VAT, you may be going down a slippery slope of not doing things properly which may eventually mean your job is also not done properly.

Agree when you intend to pay, ideally after you are satisfied with the completed job. If it is a big job agree a schedule of staged payments which is fair to both parties.

To avoid bad tradespeople and to ensure you can find them should they not answer a mobile;

Get proper contact details and check them yourself
Check if the company is verified on the Companies House website
Get phone details, ideally a land line or 0800 number and check it
Get a physical office address

Before the job starts should I agree standards of quality and behaviour?

Get quotes in writing by email or in person if possible. Getting quotes online or by text is ok (make sure you accept the offer by replying). For large projects make a written agreement, schedule of works and snagging plans as part of a working document. Also;

Agree expected quality of workmanship and materials in advance
When will work start and when will project be finished, what happens if project over runs ?
How long is the guarantee on work and materials eg 12 months
Discuss onsite behaviour in advance (no smoking, swearing or using mobile phones for non-work purposes)
Agree that your Extension Builder will remove all debris and rubbish and what level of tidying up you want after job

Compare BN1 extension builders rates

Compare BN1 extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Brighton and Hove	£35	£251
Extension Builders near Brighton	£35	£251
Extension Builders near Shoreham-by-Sea	£36	£250
Extension Builders near Burgess Hill	£36	£240
Extension Builders near Lancing	£36	£249
Extension Builders near Worthing	£35	£249
Extension Builders near Haywards Heath	£35	£256
Extension Builders near Seaford	£34	£243
Extension Builders near Mid Sussex	£35	£261
Extension Builders near Rustington	£35	£242

Job estimates from extension builders near you

Whether you’re looking to extend your kitchen with a side return extension or you want to convert your basement into a liveable space, read our cost guides to get an idea of how much each project costs before getting a more accurate quote from our database of reliable tradespeople.

Build a timber frame extension - £25,984

Garden office - £9,984

Granny annexe - £86,984

Build a flat roof extension - £21,984

Convert a Garage - £15,984

Hip to gable loft conversion - £41,984

Convert a bungalow loft - £28,984

Build a dormer loft conversion - £41,984

Build a swimming pool - £80,984

Build a Mansard loft conversion - £51,984

Concrete foundations - £6,234

Underpin a building - £17,484

Two storey extension - £87,976

Convert a basement - £37,320

Side return extension - £41,320

Loft conversion - £33,600

Garage - £18,484

Single storey extension - £54,680

Outbuilding - £9,984

Install an RSJ - £2,184

Build a kitchen extension - £41,984

More extensions & conversions cost guides...

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