
19 January 2021
Extension costs
Ever wondered how much an extension costs? We've got the latest figures from RICS to help make it that little bit clearer

In this article
There's no doubt that extensions cost a lot of money, but a lot of the time they're well worth the investment. It's always a sensible idea to get two or three quotes before you commit, but here's a general idea of costs to get you started.
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Total project costs of house extensions
House extensions size and costs | Floor size (metres) | Flat roof | Pitched roof |
Single storey with one window | 3x3 | ||
3x5 | |||
4x4 | |||
4x6 | |||
Double storey with two windows | 3x3 | ||
3x5 | |||
4x4 | |||
4x6 |
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