Build additional living space on your property in WD18

A granny annexe is the ideal solution for offering a young family member their own space in your home while they save up for their own house, or to help an older relative have some independence while keeping them at a safe distance. But how much do they cost to build in WD18?

Granny annexe cost in WD18 - Sort by rates or availability

Ferdas Design & Build Ltd

From £87,504

(last active 02/10/26)

At Ferdas Design & Build Ltd we have been fitting bespoke bathrooms since 2013. We pride ourselves on being the go-to bathroom fitters for discerni...

1 review

Torrington

From £87,192

(last active 02/10/26)

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

SH Enterprise

From £87,024

(last active 02/10/26)

Need the extension buildering job done quickly without breaking the bank? SH Enterprise offer fast, reliable, and affordable extension buildering s...

T M Builder

From £87,312

(last active 02/10/26)

Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...

Samuele Paolini

From £87,392

(last active 01/10/26)

Need an Extension Builder in WD18? Samuele Paolini has been helping local clients (5 mile radius) with their extension buildering jobs for many ye...

ABC Associates STRUCTURES 4 U

From £87,280

Member since August 2026

Relax... you have found a reliable extension builder in WD18. ABC Associates STRUCTURES 4 U is a friendly and reliable company based in WD18 who co...

VA Structures

From £87,192

(last active 01/10/26)

Need an Extension Builder in WD18? VA Structures has been helping local clients (10 mile radius) with their extension buildering jobs for many year...

DC Build & Pave

From £87,280

(last active 01/10/26)

Trusted and professional extension builder in WD18. Experienced in all extension buildering work and keeping within budget and on quote. DC Build &...

Ali & Sons Builders

From £87,152

(last active 01/10/26)

I am a qualified, builder, electrician and plumber. I have been working in the construction industry for over 23 years and have built everything fr...

The Diamond Property Service Ltd

From £87,304

(last active 01/10/26)

Hi we have 15 years of experience in building and construction industry our specialization is bathrooms and renovations please have a look at the w...

Granny Annexe Cost in WD18

Estimates for granny annexe near WD18

Building a granny annexe ranges from £87,024 (SH Enterprise based in EC1V) to £87,504 (Ferdas Design & Build Ltd based in W3), 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 WD18 by posting a job with HaMuch. We will send it to extension builders in WD18 who will be happy to help you.


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Estimates for common extension builder jobs in WD18;

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.

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