From £87,360
Need an Extension Builder in HP1? MW The Building Specialists Ltd has been helping local clients (20 mile radius) with their extension buildering j...
From £87,080
BOXMOOR BLDG & CARP SERVICES is a trusted extension builder serving customers in HP1 and the surrounding area. Contact us to today to get a competi...
From £87,040
BARRETT LESLIE BUILDING are here to help customers who need an Extension Builder in HP1. We offer a competitive rate to complete all your extension...
From £86,944
Relax... you have found a reliable extension builder in HP1. Ellis Construction is a friendly and reliable company based in HP1 who consider no job...
From £85,104
Hertfordshire brickwork is the realisation of quality and great customer service at its very best i myself the director of Hertfordshire bric...
From £87,152
JH Refurbishments are here to help customers who need an Extension Builder in HP1. We offer a competitive rate to complete all your extension build...
From £87,224
Grand Developments and Construction Ltd are here to help customers who need an Extension Builder in HP1. We offer a competitive rate to complete al...
From £87,360
Relax... you have found a reliable extension builder in HP1. Alpha Home Improvements London Ltd is a friendly and reliable company based in HP1 who...
From £87,136
Experienced extension builder ready to quote for your work. Building & Renovation Services Zdzislaw Zalewski is the best extension builder in HP1. ...
From £86,896
Simon Johnson & Sons Builders are here to help customers who need an Extension Builder in HP1. We offer a competitive rate to complete all your ext...

Building a granny annexe ranges from £85,104 (Hertfordshire brickwork based in Hp1) to £87,360 (MW The Building Specialists Ltd based in HP1), but these are just estimates that can help give you an idea of who will be better value in your area.
The best thing to do is to get quotes to build a granny annexe in HP1 by posting a job with HaMuch. We will send it to extension builders in HP1 who will be happy to help you.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Granny Annexe near Hemel Hempstead | £36 | £232 |
| Granny Annexe near Dacorum | £36 | £232 |
| Granny Annexe near Berkhamsted | £35 | £227 |
| Granny Annexe near Chesham | £36 | £237 |
| Granny Annexe near St Albans | £52 | £246 |
| Granny Annexe near Harpenden | £70 | £264 |
| Granny Annexe near Rickmansworth | £37 | £241 |
| Granny Annexe near Watford | £37 | £239 |
| Granny Annexe near Dunstable | £36 | £235 |
| Granny Annexe near Luton | £37 | £240 |
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.

Underpin a building - £17,430

Two storey extension - £87,894

Build a timber frame extension - £25,930

Build a swimming pool - £80,930

Single storey extension - £53,592

Side return extension - £40,708

Install an RSJ - £2,130

Outbuilding - £9,930

Build a Mansard loft conversion - £51,930

Loft conversion - £33,090

Build a kitchen extension - £41,930

Hip to gable loft conversion - £41,930

Granny annexe - £86,930

Garden office - £9,930

Convert a Garage - £15,930

Garage - £18,430

Build a flat roof extension - £21,930

Build a dormer loft conversion - £41,930

Concrete foundations - £6,180

Convert a bungalow loft - £28,930

Convert a basement - £36,708