From £42,560
Our homes need to be regularly maintained and from time to time they need to be rejuvenated, modernised and enhanced. When it comes to building wor...
From £41,984
JK Doors is a trusted extension builder serving customers in Harold Hill and the surrounding area. Contact us to today to get a competitive quote f...
From £42,192
NIECEIC / NAAPIT GASSAFE WATER REGULATIONS We offer services towards completion of high end construction projects to dis...
From £42,392
Need an Extension Builder in Harold Hill? Samuele Paolini has been helping local clients (5 mile radius) with their extension buildering jobs for ...
From £42,312
skilled worker who specializes in completing a wide range of building and renovation projects
From £42,616
HOUSE BUILDING SERVICES LIMITED is a trusted extension builder serving customers in Harold Hill and the surrounding area. Contact us to today to ge...
From £41,888
Member since April 2025
Trusted and professional extension builder in Harold Hill. Experienced in all extension buildering work and keeping within budget and on quote. GR ...
From £42,200
Relax... you have found a reliable extension builder in Harold Hill. Derryard Construction Ltd is a friendly and reliable company based in Harold H...
From £41,968
B J CULLEN BUILDERS are here to help customers who need an Extension Builder in Harold Hill. We offer a competitive rate to complete all your exten...
From £42,032
Relax... you have found a reliable extension builder in Harold Hill. Major Building Contractors Ltd is a friendly and reliable company based in Har...

In Harold Hill, prices for dormer loft conversions range from £41,888 (GR MAINTENANCE LTD based in IG11) to £42,616 (HOUSE BUILDING SERVICES LIMITED based in DA16), but how much your conversion costs will vary depending on the size of your property, how easy access to your roof is and what you want to use the space for.
The best way to get an accurate price is to compare quotes from extension builders in Harold Hill. Post your job on HaMuch now and we'll put you in touch with available extension builders.
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 - £17,714

Two storey extension - £88,322

Build a timber frame extension - £26,214

Build a swimming pool - £81,214

Single storey extension - £59,288

Side return extension - £43,912

Install an RSJ - £2,414

Outbuilding - £10,214

Build a Mansard loft conversion - £52,214

Loft conversion - £35,760

Build a kitchen extension - £42,214

Hip to gable loft conversion - £42,214

Granny annexe - £87,214

Garden office - £10,214

Convert a Garage - £16,214

Garage - £18,714

Build a flat roof extension - £22,214

Build a dormer loft conversion - £42,214

Concrete foundations - £6,464

Convert a bungalow loft - £29,214

Convert a basement - £39,912