1 review
From £10,192
NIECEIC / NAAPIT GASSAFE WATER REGULATIONS We offer services towards completion of high end construction projects to dis...
"Did callout made safe my elctrical work thanks" - reviewed 16/05/23, REECYRUSSO
From £10,024
Need the extension buildering job done quickly without breaking the bank? SH Enterprise offer fast, reliable, and affordable extension buildering s...
From £10,008
Over 35 years experience
We are Gas Safe registered
We are Verified
We pride ourselves on great custom...
From £10,312
Local Boiler Plumbing & Heating Services is an established and experienced local extension builder in CM15. Please contact us for a free, no obliga...
From £10,184
Experienced extension builder ready to quote for your work. CC&D BUILDING LTD is the best extension builder in CM15. No obligation free quotes and ...
From £10,184
Relax... you have found a reliable extension builder in CM15. First guard Roofing is a friendly and reliable company based in CM15 who consider no ...
From £10,616
HOUSE BUILDING SERVICES LIMITED is a trusted extension builder serving customers in CM15 and the surrounding area. Contact us to today to get a com...
From £9,880
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 £10,248
At Building Services Contractors we pride ourselves on an efficient and friendly service, and strive to achieve 100% customer satisfaction.
From £11,584
Propello is an established and experienced local extension builder in CM15. Please contact us for a free, no obligation quote and competitive rate...

Outbuilding costs in CM15 range from the cheapest of £9,880 (Can design and Construction based in Ig11) to the dearest of £11,584 (Propello based in E17), but these are just estimates.
Comparing extension builders estimates for building an outbuilding gives you an idea of who will be better value, but the best way to compare costs is to get actual quotes.
Get rates and quotes to build an outbuilding in CM15 by posting a job with HaMuch and we will send it to extension builders.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Outbuilding near Brentwood | £39 | £255 |
| Outbuilding near Billericay | £38 | £248 |
| Outbuilding near Romford | £45 | £274 |
| Outbuilding near Basildon | £39 | £251 |
| Outbuilding near South Ockendon | £58 | £276 |
| Outbuilding near Chelmsford | £38 | £258 |
| Outbuilding near Wickford | £39 | £255 |
| Outbuilding near Stanford-le-Hope | £40 | £254 |
| Outbuilding near Loughton | £44 | £273 |
| Outbuilding near Thurrock | £41 | £260 |
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 - £17,823

Two storey extension - £88,485

Build a timber frame extension - £26,323

Build a swimming pool - £81,323

Single storey extension - £61,464

Side return extension - £45,136

Install an RSJ - £2,523

Outbuilding - £10,323

Build a Mansard loft conversion - £52,323

Loft conversion - £36,780

Build a kitchen extension - £42,323

Hip to gable loft conversion - £42,323

Granny annexe - £87,323

Garden office - £10,323

Convert a Garage - £16,323

Garage - £18,823

Build a flat roof extension - £22,323

Build a dormer loft conversion - £42,323

Concrete foundations - £6,573

Convert a bungalow loft - £29,323

Convert a basement - £41,136