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Home & garden.

Updated: 2 Nov 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
Rachel Christie
Extension plans_jul19 483003

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 costsFloor size (metres)Flat roofPitched roof
Single storey with one window3x3
Double storey with two windows3x3
Home finances and extension costs

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