Extension Value Calculator UK

Undertaking a home extension is a big task, and for many people, the cost will be a deciding factor. It's important to know how much value an extension will add to your home. This can help you make sure that adding your new kitchen, bedroom, or bathroom is worth it.

Knowing the value of an extension and how it will improve your property is important when you get a mortgage or loan to cover the extension costs. You'll want to ensure that the amount you're borrowing is covered by the additional value that it brings to your property.

If you're looking for an estimate on how much your extension will add, you can use this home extension calculator to help.

Once you’ve estimated how much value your extension will add to your house, read our guide to funding home improvements to get started on improving your home.

It’s important to remember that the value an extension could add to your home will vary depending on a number of factors from the quality of construction, to the type of room - including whether it’s a kitchen extension or adding an extra bedroom - and the exact location of your property. This calculator provides an indication of how much you could add to your property by drawing on the average value of houses across local authority areas.

The house extension calculator below uses data from the Office of National Statistics, looking at property prices per square metre in England and Wales. It will indicate how much value an extension could add to your home.

Considering a home extension? Perhaps you want to extend your kitchen or bathroom or add an extra bedroom? Simply enter where you live and the size of the extension you’re looking to add and we’ll help you work out what an extension could add to the value of your home.

Our extension calculator is based on the size of your extension as well as where you live. There are, of course, other factors that will decide the exact value that an extension adds - such as how the extension may affect your garden or another area of the house, how the natural lighting will be affected etc. You should make sure you have considered these before starting your extension.

Remortgage

If you’re at the end of a fixed term mortgage you could remortgage to release some of the equity in your property. Compare remortgage deals with our free best buys tool. This can help get you the funds to build an extension on your home.

Second Charge Mortgage

Second charge mortgages, secured loans, or homeowner loans as they're sometimes known, are called second mortgages because they have secondary priority behind your main (or first-charge) mortgage.

They're a secured loan, which means they use the borrower’s home as security and are popular for those tied into their current mortgage who aim to repay the second charge via a remortgage when the main deal expires.