From £87,176
Trusted and professional extension builder in BN25. Experienced in all extension buildering work and keeping within budget and on quote. J L BUILDI...
From £87,288
Oliver Relton
Here at Complete Property Solutions, we have a small dedicated team of professional, conscientious tradesman with the knowledge and experience to e...
From £86,808
The Place Between offers home design and project management services. We work with a network of building professionals. We believe that the transit...
From £87,064
At Prestige we pride ourselves on delivering bespoke projects including Heritage and specialist works.

Building a granny annexe ranges from £86,808 (The Place Between based in BN25) to £87,288 (Complete Property Solutions (Sussex) Limited based in BN9), 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 BN25 by posting a job with HaMuch. We will send it to extension builders in BN25 who will be happy to help you.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Granny Annexe near Seaford | £34 | £243 |
| Granny Annexe near Eastbourne | £32 | £245 |
| Granny Annexe near Hailsham | £31 | £243 |
| Granny Annexe near Brighton and Hove | £35 | £251 |
| Granny Annexe near Brighton | £35 | £251 |
| Granny Annexe near Wealden | £35 | £256 |
| Granny Annexe near Burgess Hill | £36 | £240 |
| Granny Annexe near Shoreham-by-Sea | £36 | £250 |
| Granny Annexe near Bexhill-on-Sea | £31 | £243 |
| Granny Annexe near Haywards Heath | £35 | £256 |
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 - £17,584

Two storey extension - £88,126

Build a timber frame extension - £26,084

Build a swimming pool - £81,084

Single storey extension - £56,680

Side return extension - £42,445

Install an RSJ - £2,284

Outbuilding - £10,084

Build a Mansard loft conversion - £52,084

Loft conversion - £34,538

Build a kitchen extension - £42,084

Hip to gable loft conversion - £42,084

Granny annexe - £87,084

Garden office - £10,084

Convert a Garage - £16,084

Garage - £18,584

Build a flat roof extension - £22,084

Build a dormer loft conversion - £42,084

Concrete foundations - £6,334

Convert a bungalow loft - £29,084

Convert a basement - £38,445