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Home & garden.

30 June 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
RC
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 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
Home finances and extension costs

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