Extension builder estimates (based on hourly rates) to build a single storey extension in Welwyn Garden City
Range from the cheapest single storey extension £34000 (Complex Construction based in AL7) to the dearest single storey extension £49680 (Floorplan Ltd based in sg4).
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 Welwyn Garden City by posting a job with HaMuch and we will send it to extension builders in Welwyn Garden City.
Estimates for common extension builder jobs in Welwyn Garden City;
| Job | Estimate |
| Underpinning a house | £17361 |
| Build a two storey extension | £87791 |
| Build a timber frame extension | £25861 |
| Install a swimming pool | £80861 |
| Cost to build a single storey extension | £47216 |
| Cost to build a side return extension | £35934 |
| Install an RSJ | £2061 |
| Build an outbuilding | £9861 |
| Build a mansard loft conversion | £51861 |
| Cost of a loft conversion | £32445 |
| Build a kitchen extension | £41861 |
| Build a hip to gable loft conversion | £41861 |
| Build a granny annexe | £86861 |
| Build a garden office | £9861 |
| Convert a garage | £15861 |
| Build a new garage | £18361 |
| Build a flat roof extension | £21861 |
| Build a dormer loft conversion | £41861 |
| Lay a concrete foundation | £6111 |
| Convert a bungalow loft | £28861 |
| Basement conversion cost | £35934 |