From £86,880
Experienced extension builder ready to quote for your work. CIA Construction Limited is the best extension builder in CM4. No obligation free quote...
From £87,064
Hyde Building Ltd are here to help customers who need an Extension Builder in CM4. We offer a competitive rate to complete all your extension build...
From £87,360
Need an Extension Builder in CM4? Ellis & James Builders Limited has been helping local clients (20 mile radius) with their extension buildering jo...
From £87,008
Over 35 years experience
We are Gas Safe registered
We are Verified
We pride ourselves on great custom...
From £87,312
Local Boiler Plumbing & Heating Services is an established and experienced local extension builder in CM4. Please contact us for a free, no obligat...
From £87,184
Experienced extension builder ready to quote for your work. CC&D BUILDING LTD is the best extension builder in CM4. No obligation free quotes and m...
From £87,616
HOUSE BUILDING SERVICES LIMITED is a trusted extension builder serving customers in CM4 and the surrounding area. Contact us to today to get a comp...
From £86,880
Member since August 2025
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £88,584
Propello is an established and experienced local extension builder in CM4. Please contact us for a free, no obligation quote and competitive rates...
From £87,424
Nouvell Decor is a trusted extension builder serving customers in CM4 and the surrounding area. Contact us to today to get a competitive quote for ...

Building a granny annexe ranges from £86,880 (CIA Construction Limited based in RM18) to £88,584 (Propello based in E17), 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 CM4 by posting a job with HaMuch. We will send it to extension builders in CM4 who will be happy to help you.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Granny Annexe near Billericay | £38 | £248 |
| Granny Annexe near Brentwood | £39 | £255 |
| Granny Annexe near Chelmsford | £38 | £258 |
| Granny Annexe near Wickford | £39 | £255 |
| Granny Annexe near Basildon | £39 | £251 |
| Granny Annexe near Stanford-le-Hope | £40 | £254 |
| Granny Annexe near Romford | £45 | £274 |
| Granny Annexe near Rayleigh | £39 | £252 |
| Granny Annexe near Thundersley | £38 | £251 |
| Granny Annexe near South Ockendon | £58 | £276 |
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 - £17,831

Two storey extension - £88,497

Build a timber frame extension - £26,331

Build a swimming pool - £81,331

Single storey extension - £61,624

Side return extension - £45,226

Install an RSJ - £2,531

Outbuilding - £10,331

Build a Mansard loft conversion - £52,331

Loft conversion - £36,855

Build a kitchen extension - £42,331

Hip to gable loft conversion - £42,331

Granny annexe - £87,331

Garden office - £10,331

Convert a Garage - £16,331

Garage - £18,831

Build a flat roof extension - £22,331

Build a dormer loft conversion - £42,331

Concrete foundations - £6,581

Convert a bungalow loft - £29,331

Convert a basement - £41,226