From £86,976
Grand Homes Developments is an established extension buildering business in SL3. We come highly recommended and provide competitive quotes for your...
From £87,008
Blue Sky Roofing and Home Improvements is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get...
From £87,080
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £87,336
Tom's Builders is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get a competitive quote for...
From £87,064
MRE Maintenance Services is an established and experienced local extension builder in SL3. Please contact us for a free, no obligation quote and co...
From £86,664
I have been in the building trade since I was 14 I've learnt from my father's employees and so on and I know experience is the key to a good job wi...
From £87,144
BDR Home Improvement are here to help customers who need an Extension Builder in SL3. We offer a competitive rate to complete all your extension bu...
From £86,544
Drains R Uss is a trusted extension builder serving customers in SL3 and the surrounding area. Contact us to today to get a competitive quote for e...
From £86,808
Relax... you have found a reliable extension builder in SL3. C WINTER BUILDING SERVICES is a friendly and reliable company based in SL3 who conside...
From £87,224
Experienced extension builder ready to quote for your work. My Garage Makeover (UK) is the best extension builder in SL3. No obligation free quotes...

Building a granny annexe ranges from £86,544 (Drains R Uss based in SL3) to £87,336 (Tom's Builders based in SL3), 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 SL3 by posting a job with HaMuch. We will send it to extension builders in SL3 who will be happy to help you.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Granny Annexe near Slough | £42 | £272 |
| Granny Annexe near Windsor & Maidenhead | £42 | £272 |
| Granny Annexe near Windsor | £41 | £271 |
| Granny Annexe near Staines-upon-Thames | £42 | £269 |
| Granny Annexe near Egham | £42 | £266 |
| Granny Annexe near Hillingdon | £62 | £276 |
| Granny Annexe near Gerrards Cross | £43 | £282 |
| Granny Annexe near Maidenhead | £41 | £273 |
| Granny Annexe near Ascot | £41 | £276 |
| Granny Annexe near Sunbury-on-Thames | £42 | £279 |
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 - £17,485

Two storey extension - £87,977

Build a timber frame extension - £25,985

Build a swimming pool - £80,985

Single storey extension - £54,696

Side return extension - £41,329

Install an RSJ - £2,185

Outbuilding - £9,985

Build a Mansard loft conversion - £51,985

Loft conversion - £33,608

Build a kitchen extension - £41,985

Hip to gable loft conversion - £41,985

Granny annexe - £86,985

Garden office - £9,985

Convert a Garage - £15,985

Garage - £18,485

Build a flat roof extension - £21,985

Build a dormer loft conversion - £41,985

Concrete foundations - £6,235

Convert a bungalow loft - £28,985

Convert a basement - £37,329