How much does a house extension cost?
Our clients:, we are often asked ‘How much will an extension to my house cost?’. We know that when designing, clients are most interested in the build budget. But there are actually three main factors when choosing a design and build company – easy, speedy and cost certainty.
In brief, most extension projects cost around £1750-£2750 per square metre. So if you want to add a 30m² kitchen extension it could cost £52,500-£82,500, plus 20% VAT.
You should realise that this is an approximate cost. This is the maximum we can tell you, we have no details or ideas of what the extension looks like, what materials you are going to use, how it will be built. However, the price of £1750 to £2750 – gives an idea of the price range based on averages.
Many factors can affect the cost of your project, including:
The number of storeys you intend to build.
Size and shape of the extension.
The quality and cost of construction materials.
The length of construction, and your involvement in the project.
The amount of glazing you would like to have.
Whether the extension will have a kitchen or bathroom, and the availability of heating.
What other costs are there?
Here are some examples of costs you will need to consider:
– Architect’s fees.
– Structural engineer (around £500-£1,500).
– Survey (around £700-£1,800).
– Planning permission (if required – currently £258 for a homeowner, in England for a two storey extension.
– Lawful Development Certificate (currently £103).
– Building Regulations application (around £800-£1,800).
– Fit-out of the extension (the cost depends on how you plan to use the new premises).
– Agreement to build a wall (£1,000 to £2,000 per affected neighbour for a simple agreement outside London if required).
– Insurance.
Do you pay VAT on extensions?
Building work to extend an existing home is normally subject to VAT at the standard rate of 20%. If you are building a brand new home, you are exempt from VAT.
Building work on certain extension projects qualify for a reduced rate of VAT, currently 5%. These include extensions that are part of:
– the conversion of an existing dwelling with a change in the number of units.
– works to a building that has not been occupied for at least two years.
To take advantage of VAT relief, you must employ the services of a VAT registered builder – you will not be able to claim VAT on your own.
Will an extension increase the value of my home?
In financial terms, opting for even a small extension to your home means you’ll save on moving house, stay in a familiar neighbourhood, and save on solicitors’ fees and stamp duty. However, be aware that increasing the square footage of your home could lead to higher income tax.
If you’re planning to sell your home – either soon or in the future – you need to make sure you add more value to it than the extension is worth. Talk to local estate agents and research house prices in the area before you decide to go ahead with an extension.
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