Planning your development Typical improvement costs
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This article, Planning your development, was last updated on 31 March 2008 and is now out of date and held in our online archive for reference. Explore our latest Home & garden articles.
Home improvement costs are notoriously difficult to predict or estimate. The figures in this table are purely for guidance as every home is different.
| Examples of home improvement costs | |||
|---|---|---|---|
| Work carried out | Guide price (per square metre) | Budget/easy | Premium/bespoke |
| Building | |||
| One-storey extension | £550 – £1,250 | £7,000 | £35,000 |
| Two-storey extension | £800 – £2,000 | £15,000 | £50,000 |
| Garage | Self-build: £20–£50 | £1,000 | £8,000 |
| Garage | Built: £200 – £500 | £5,000 | £40,000 |
| Conservatory | £225 – £3,000 | £6,000 | £35,000 |
| Basement | £1,000 – £2,500 | £40,000 | £100,000 |
| Conversion | |||
| Loft | £750 – £2,000 | £18,000 | £50,000 |
| Garage | £400 – £1,000 | £9,000 | £25,000 |
| Basement | £500 – £2,500 | £10,000 | £50,000 |
| Additions | |||
| Garden building (summer house/office) | £70 – £250 | £1,000 | £20,000 |
| External work | |||
| Roofing | £45 – £100 | —- | —- |
| Windows | £350 – £1,000 eacha | —- | —- |
| External doors | £100 – £500 eacha | —- | —- |
| Internal work | |||
| Internal doors | £30 – £300 eacha | —- | —- |
| Boiler | £400 – £1,200 each | —- | —- |
| Radiators | £50 – £500 each | —- | —- |
| Wiring | N/A | £2,000 | £7,000 |
Table notes
- Sum includes furniture and fitting
Budget/Easy
This is the minimum price for a home improvement, where labour rates for the work are low. The improvement would be small scale and only require standard building practices and materials. For example, a one-storey extension 3 x 1m built on standard foundations using cheapest brick or brick/block, which is easy to join to the current roof structure.
Premium/Bespoke
These prices are for areas that have high labour rates and for large-scale improvements or where additional work is required. For example, a 3 x 3m extension in a conservation area that requires more expensive materials to be used or additional work, such as moving drains or the extension requiring specialist foundations.
