HOW MUCH DOES A HOUSE EXTENSION COST
Every house extension project featured in my portfolio has the construction cost for 2024 listed in the information, so you can see what it would take to build that project today. I have run Capital A since 2009 and have built dozens of projects across Edinburgh, the Lothians and Fife in that time. I have used that experience to set out a simple guide to typical house extension projects below.
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Keep in mind that VAT applies to all refurbishment, repairs, alterations and extensions to homes in the UK. The costs listed here make assumptions about the amount of internal work required to the existing house, as well as the likely cost of new kitchens, bathrooms, flooring and glazing etc. I offer a free constulaion service, so I can give you more accurate advice if you contact me.
This extension measures 4m x 4m
There is no work planned inside the existing house.
An exiting door in the side wall of the house is used to connect the new structure to the house.
The existing garage will remain as storage.
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The basic construction cost for this extension would start at £43k + VAT but could easily cost more than £55k + VAT if higher quality fittings were included or the structural work to join the extension to the house involved forming a new opening in the external wall.
This extension measures 4m x 5m
There is no work planned inside the existing house.
An exiting door in the side wall of the house is used to connect the new structure to the house.
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The basic construction cost for this extension would start at £58k + VAT but could easily cost more than £65k + VAT if higher quality fittings were included or the structural work to join the extension to the house involved forming a new opening in the external wall.
This extension measures 45 square meters.
New openings are formed in existing external wall of the house.
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The basic construction cost for this extension would start at £150k + VAT but could easily cost more than £200k + VAT if this includes new kitchen units, large areas of glazing or high end internal finishes.
This extension measures 5m x 4m
The internal layout of both floors in the existing house will be altered to integrate the new house extension with the existing layout.
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The basic construction cost for this extension would start at £200k + VAT but could easily cost more than £300k + VAT if this includes new kitchen units, large areas of glazing or high end internal finishes. A significant portion of the budget will be required to carry out work inside the existing house.
