From £86,704
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £86,824
Need an Extension Builder in Mountain Ash? FORMWORK CONSTRUCTION LTD has been helping local clients (20 mile radius) with their extension builderin...
From £86,896
Barlam Drylining Ltd are here to help customers who need an Extension Builder in Mountain Ash. We offer a competitive rate to complete all your ext...
From £86,848
Relax... you have found a reliable extension builder in Mountain Ash. Professional Concrete Solutions is a friendly and reliable company based in M...
From £86,528
Need an Extension Builder in Mountain Ash? A POWELL CONSTRUCTION LTD has been helping local clients (20 mile radius) with their extension builderin...
From £86,576
L E JONES BUILDER is an established extension buildering business in Mountain Ash. We come highly recommended and provide competitive quotes for yo...
From £86,496
Trusted and professional extension builder in Mountain Ash. Experienced in all extension buildering work and keeping within budget and on quote. RJ...
From £86,808
Dare Fitness is an established extension buildering business in Mountain Ash. We come highly recommended and provide competitive quotes for your wo...
From £86,800
Need an Extension Builder in Mountain Ash? MG3Design has been helping local clients (20 mile radius) with their extension buildering jobs for many ...
From £86,552
P ALLEN BUILDERS is an established and experienced local extension builder in Mountain Ash. Please contact us for a free, no obligation quote and c...

Building a granny annexe ranges from £86,496 (RJ CONSTRUCTION based in CF40) to £86,896 (Barlam Drylining Ltd based in CF45), 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 Mountain Ash by posting a job with HaMuch. We will send it to extension builders in Mountain Ash who will be happy to help you.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Granny Annexe near Rhondda, Cynon, Taff | £27 | £183 |
| Granny Annexe near Rhondda | £27 | £183 |
| Granny Annexe near Pontypridd | £29 | £184 |
| Granny Annexe near Aberdare | £28 | £186 |
| Granny Annexe near Merthyr Tydfil | £28 | £187 |
| Granny Annexe near Church Village | £30 | £188 |
| Granny Annexe near Tredegar | £24 | £195 |
| Granny Annexe near Caerphilly | £29 | £181 |
| Granny Annexe near Ebbw Vale | £24 | £195 |
| Granny Annexe near Risca | £27 | £185 |
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 - £17,203

Two storey extension - £87,555

Build a timber frame extension - £25,703

Build a swimming pool - £80,703

Single storey extension - £49,064

Side return extension - £38,161

Install an RSJ - £1,903

Outbuilding - £9,703

Build a Mansard loft conversion - £51,703

Loft conversion - £30,968

Build a kitchen extension - £41,703

Hip to gable loft conversion - £41,703

Granny annexe - £86,703

Garden office - £9,703

Convert a Garage - £15,703

Garage - £18,203

Build a flat roof extension - £21,703

Build a dormer loft conversion - £41,703

Concrete foundations - £5,953

Convert a bungalow loft - £28,703

Convert a basement - £34,161