Extension builder estimates (based on hourly rates) to build a single storey extension in City Of Westminster
Range from the cheapest single storey extension £13200 (London Design And Build based in SW1A) to the dearest single storey extension £48880 (Mayfair Design based in W1J).
Comparing extension builders estimates for fitting a downstairs toilet gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
What to do - Get rates and quotes to build a single storey extension in City Of Westminster by posting a job with HaMuch and we will send it to extension builders in City Of Westminster.
Estimates for common extension builder jobs in City Of Westminster;
| Job | Estimate |
| Underpinning a house | £17321 |
| Build a two storey extension | £87731 |
| Build a timber frame extension | £25821 |
| Install a swimming pool | £80821 |
| Cost to build a single storey extension | £46416 |
| Cost to build a side return extension | £35484 |
| Install an RSJ | £2021 |
| Build an outbuilding | £9821 |
| Build a mansard loft conversion | £51821 |
| Cost of a loft conversion | £32070 |
| Build a kitchen extension | £41821 |
| Build a hip to gable loft conversion | £41821 |
| Build a granny annexe | £86821 |
| Build a garden office | £9821 |
| Convert a garage | £15821 |
| Build a new garage | £18321 |
| Build a flat roof extension | £21821 |
| Build a dormer loft conversion | £41821 |
| Lay a concrete foundation | £6071 |
| Convert a bungalow loft | £28821 |
| Basement conversion cost | £35484 |