From £42,048
Experienced extension builder ready to quote for your work. J&J Building Solutions is the best extension builder in Archway. No obligation free quo...
From £42,312
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £42,200
Relax... you have found a reliable extension builder in Archway. Derryard Construction Ltd is a friendly and reliable company based in Archway who ...
From £41,968
B J CULLEN BUILDERS are here to help customers who need an Extension Builder in Archway. We offer a competitive rate to complete all your extension...
From £42,032
Relax... you have found a reliable extension builder in Archway. Major Building Contractors Ltd is a friendly and reliable company based in Archway...
From £42,184
Need to find an Extension Builder near you for all your extension buildering work?
Sz Builders provides a local, trusted extension builderi...
From £42,712
Experienced extension builder ready to quote for your work. Render is the best extension builder in Archway. No obligation free quotes and many hap...
From £41,896
Experienced extension builder ready to quote for your work. Jhon is the best extension builder in Archway. No obligation free quotes and many happy...
From £41,880
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 £42,192
NIECEIC / NAAPIT GASSAFE WATER REGULATIONS We offer services towards completion of high end construction projects to dis...

In Archway, prices for dormer loft conversions range from £41,880 (Can design and Construction based in Ig11) to £42,712 (Render based in IG1), 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 Archway. 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 - £17,642

Two storey extension - £88,214

Build a timber frame extension - £26,142

Build a swimming pool - £81,142

Single storey extension - £57,848

Side return extension - £43,102

Install an RSJ - £2,342

Outbuilding - £10,142

Build a Mansard loft conversion - £52,142

Loft conversion - £35,085

Build a kitchen extension - £42,142

Hip to gable loft conversion - £42,142

Granny annexe - £87,142

Garden office - £10,142

Convert a Garage - £16,142

Garage - £18,642

Build a flat roof extension - £22,142

Build a dormer loft conversion - £42,142

Concrete foundations - £6,392

Convert a bungalow loft - £29,142

Convert a basement - £39,102