We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies. You can understand more and change your cookies preferences here.

Should you extend your home or buy a bigger property?

Cost of upsizing from a semi to detached home drops in 2019

An increasing number of homeowners are improving their properties rather than upsizing, but is it really harder than before to progress up the property ladder?

A new report by TSB found that a fifth of owners are considering extending their homes, with the sky-high cost of moving to a bigger property one of the biggest factors.

We’ve crunched the numbers to assess just how expensive it is to upsize to a bigger home depending on where you live, and offer advice on whether you’re better off sprucing up your current property instead.


Homeowners put off by cost of moving

Research by TSB says homeowners are being spurred on to extend their properties by a recent relaxation in planning laws, which now allow people to add rear extensions to their homes without planning permission.

As a result, one in five homeowners say they are likely to extend their home within the next three years. Owners cite an attachment to their current house (50%), the cost of moving home (49%) and their property’s location (25%) as their key reasons for staying put.

Aside from the emotional pain of leaving a property they love, it’s easy to see why homeowners are put off by the cost of moving, with additional costs such as stamp duty and legal fees potentially adding thousands of pounds to their bills.

How much does it cost to upsize?

So just how expensive is it to take your next step up the property ladder?

In truth, the cost depends on where you live, from tens of thousands of pounds in some regions to hundreds of thousands in London and the South East of England.

We’ve analysed data from the Land Registry to show the cost of upgrading to a bigger property, and assess whether it’s getting cheaper or more expensive to take the leap.

Flat to semi-detached

The cost of upgrading from a flat to a semi-detached home varies from just under £40,000 in Wales to nearly £160,000 in London.

The bad news is that homeowners now need more money to upsize, with the price of moving increasing in every region except London in the last 12 months.

The biggest percentage increases were seen in Yorkshire & The Humber, Scotland, and Wales, where the gap in cost between a flat and a semi rose by 10%.

Region Upgrade price (2018) Upgrade price (2019) Difference
Yorkshire & The Humber £43,668 £48,305 10%
Scotland £46,004 £50,556 10%
Wales £39,706 £43,634 10%
North West £50,848 £55,598 9%
South West £90,032 £96,208 7%
East of England £100,640 £106,255 6%
North East £40,809 £42,867 5%
South East £140,711 £146,793 4%
West Midlands £61,174 £63,879 4%
London £167,460 £159,547 -4%

Semi-detached to detached

If you’re living in a semi-detached property and are looking to upgrade to a detached home, there’s good and bad news.

The bad news is that in all bar three regions (North East of England, Wales and Yorkshire & The Humber), the cost of upsizing is more than £100,000, or more than £200,000 in London and the South East of England.

The good news, however, is that this gap is narrowing. With the exception of Scotland and the North West, it’s now cheaper to upsize than it was a year ago.

London saw the biggest change, with the price of upgrading falling by 14% – though upsizers will still need to find an additional £290,000.

Elsewhere, the North East of England saw the most significant falls, with the additional cost of moving to a detached home falling from £88,000 to £81,000.

Region Upgrade price (2018) Upgrade price (2019) Difference
Scotland £98,942 £102,341 3%
North West £108,186 £108,601 <1%
Yorkshire & The Humber £101,161 £99,755 -1%
Wales £87,496 £84,756 -3%
East of England £143,627 £138,372 -4%
South West £138,846 £133,336 -4%
East Midlands £105,548 £100,300 -5%
South East £216,884 £206,634 -5%
North East £88,134 £81,681 -7%
London £336,826 £289,439 -14%


The cost of home improvements

If you’re looking to stay and extend your home, you might be wondering how much you’ll need to spend.

Of course, home improvements come in many shapes and sizes, from energy-efficient measures such as installing insulation and double glazing to more serious projects such as loft conversions, so you’ll need to do your research. As a very broad guide, here are some indications of what you might pay for four popular renovations:

  • Kitchen improvements: having a new kitchen fitted could cost you anything from £14,000 to £40,000. Bespoke models could set you back double this price.
  • Replacing windows: double glazing comes in all shapes and sizes, with individual windows costing from around £500 to several thousand pounds. To buy and hang a double-glazed interior door, you can expect to pay £400-£800.
  • Conservatories: adding a conservatory is one of the more expensive home improvements you can make, with prices ranging from around £14,000 to £40,000.
  • Loft conversions: these can add extra space and value to your home, though the price of a loft conversion varies significantly depending on the size and complexity of the project. Expect to pay anything from £20,000 to £65,000.

Sign up for a Which? trial for advice on home improvements

Which? members can find out more about the specific costs of renovating in our full guides on home improvements.

To access thousands of product reviews and our comprehensive online advice content, take out a £1 trial to Which? Magazine.


How to finance home improvements

How you finance your home improvement will depend on your financial circumstances and the cost of the renovation.

TSB’s research shows that 35% of homeowners would consider remortgaging to extend their properties – an option that’s becoming more popular.

Data from trade body UK Finance shows that 16,880 people remortgaged their home to take on additional borrowing in June – that’s a rise of 8% year-on-year. This reflects homeowners taking advantage of attractive mortgage rates while they last.

Alternatively, you could consider using existing savings, a personal loan or a credit card that offers 0% interest on purchases – right now the longest interest-free deal is 26 months.

Budgeting for home improvements

When planning renovation work, it’s important to lock down a budget and try to stick to it, as costs can spiral.

In January, Which? asked 682 homeowners about their recent home renovations. A third said the cost ended up being slightly higher than they expected, while 16% said the final bill was considerably more expensive.

Additionally, research we conducted last year found that double-height extensions, open-plan spaces, single-height extensions, loft conversions and garage conversions were the renovations most likely to blow the budget.

Advice on home improvements

Before extending your home, it’s important to think about whether your investment is likely to pay dividends in the long-run.

James Ginley of Legal & General Surveying Services says: ‘Where space is at a premium, quite simply adding floor area adds value. However, good design, layout and functionality of homes is increasingly important.

‘Home buyers want the space, but tasteful extensions and modern open-plan living areas offered by extensions can generate value.’

Back to top
Back to top