Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.64 (7 reviews)

Find affordable HP4 extension builders

Cheapest £25/hour & £13/day (Hertfordshire brickwork) to £47/hour & £307/day (COWMAN CONSTRUCTION) - average £41/hour & £261/day

Local HP4 extension builders with reviews/jobs - Sort by rates or availability

"Kitchen extension" - HEMEL HEMPSTEAD, job posted 21/09/25

"Single storey extension" - HEMEL HEMPSTEAD, job posted 07/09/25

"Single storey extension" - HEMEL HEMPSTEAD, job posted 19/04/25

"Loft conversion" - HEMEL HEMPST, job posted 02/02/25

"Loft conversion" - DACORUM, job posted 24/06/24

"Loft conversion Loft conversion" - DACORUM, job posted 03/06/24

"Single storey extension" - CHESHAM, job posted 06/03/24

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 HP4 extension builders rates

Compare HP4 extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Berkhamsted	£41	£263
Extension Builders near Dacorum	£42	£269
Extension Builders near Hemel Hempstead	£42	£270
Extension Builders near Chesham	£42	£277
Extension Builders near Dunstable	£41	£272
Extension Builders near Rickmansworth	£42	£278
Extension Builders near St Albans	£63	£288
Extension Builders near Harpenden	£86	£315
Extension Builders near Hazlemere	£40	£272
Extension Builders near Luton	£41	£278

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 - £26,088

Garden office - £10,088

Granny annexe - £87,088

Build a flat roof extension - £22,088

Convert a Garage - £16,088

Hip to gable loft conversion - £42,088

Convert a bungalow loft - £29,088

Build a dormer loft conversion - £42,088

Build a swimming pool - £81,088

Build a Mansard loft conversion - £52,088

Concrete foundations - £6,338

Underpin a building - £17,588

Two storey extension - £88,132

Convert a basement - £38,490

Side return extension - £42,490

Loft conversion - £34,575

Garage - £18,588

Single storey extension - £56,760

Outbuilding - £10,088

Install an RSJ - £2,288

Build a kitchen extension - £42,088

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