How Much Does It Cost To Build An Extension?

How Much Does It Cost To Build An Extension
Home expansion cost per square metre – Extensions are difficult projects that include a number of various parts and trades, from establishing foundations and constructing walls to plastering, electrics, and plumbing – and that’s before finishing touches like installing a new kitchen! Expenses can be affected by a variety of factors, such as ease of access and your choice of kitchen counter, but the fundamental costs are determined by the size and quality of your construction, as shown below:

Small (3mx5m) Medium (4mx6m) Large (6mx8m)
Basic £14-£18.5k £22-30k £44-60k
Standard £18.5-£24k £30-£39k £60-£77k
Premium £24-£34.5k £39-£55k £77-£115k

In this post, we have broken down the various components of an extension build and the associated expenses, but the primary cost driver is the size of the addition being constructed. According to our specialists, the base cost per square meter for constructing an addition is between £1,300 and £1,600.

  1. Therefore, the price range for a 20msq addition (4m x 5m) is between £25,500 and £32,500.
  2. These prices do not include the 20% VAT.
  3. The price range reflects the variety of materials used, the intricacy of the design, the quality of the finish, and your location in the United Kingdom.
  4. This price includes the construction of the foundation, the walls, the insulation of the new structure, the installation of plasterboard and a flooring, and the installation of a basic plumbing and electrical system.

It does not include any of the finishing touches, like as décor or kitchen installation, which we will discuss later in the article.

How much does it cost to extend a property in the United Kingdom?

Home expansion cost per square metre – Extensions are difficult projects that include a number of various parts and trades, from establishing foundations and constructing walls to plastering, electrics, and plumbing – and that’s before finishing touches like installing a new kitchen! Expenses can be affected by a variety of factors, such as ease of access and your choice of kitchen counter, but the fundamental costs are determined by the size and quality of your construction, as shown below:

Small (3mx5m) Medium (4mx6m) Large (6mx8m)
Basic £14-£18.5k £22-30k £44-60k
Standard £18.5-£24k £30-£39k £60-£77k
Premium £24-£34.5k £39-£55k £77-£115k

While we’ve broken out many construction-related expenses and aspects in this post, the size of the expansion being built is the primary underlying cost. According to our specialists, the cost of constructing an addition ranges from £1,300 to £1,600 per square meter.

How Much Does an Extension Cost? – The price of an extension varies greatly based on its size and intended usage. The most economical extensions are typically the smaller, simpler ones. The following list of typical extension kinds includes their costs, ranging from low to high, as well as the time needed to accomplish them.

Extension Type Budget (per sqm) Mid-range (per sqm) Luxury (per sqm) Time Required
Single-storey Extension £1,000 to £1,600 £1,700 to £2,000 £2,200 to £4,000 and up 8 to 10 weeks
Two-storey Extension £1,200 to £1,900 £2,000 to £2,200 £2,300 to £4,000 and up 12 to 16 weeks
Side Return Extension £1,500 to £1,900 £1,900 to £2,200 £2,200 to £2,500 10 to 12 weeks
Glass Extension £1,350 to £1,950 £1,800 to £2,300 £3,000 and up 10 to 12 weeks
Flat Pack Extension £750 to £1,440 £1,275 to £1,800 £1,650 to £3,600 1 to 2 weeks

For a single-storey addition, you can anticipate it to cost between £1,000 to £1,600 at the cheaper end of the pricing range, £1,700 to £2,000 for the mid-range and £2,200 to £4,000 and up at the luxury end of the price range. You may expect this structure to be pretty easy and box-shaped as a single-storey.

  • A two-storey expansion is expected to cost £1,200 to £1,900 at the lower end of the pricing range, £2,000 to £2,200 for a mid-range extension and £2,300 to £4,000 and up for a luxury two-storey extension.
  • A two-storey expansion isn’t going to cost that much more than a single-storey as you’ll merely be installing extra joists and walls.

A cheap side-return expansion is predicted to cost £1,500 to £1,900, £1,900 to £2,200 for a mid-range extension and £2,200 to £2,500 for a premium side-return extension. A cheap glass expansion is estimated to cost £1,350 to £1,950, with a mid-range glass extension costing £1,800 to £2,300 and a premium range to cost £3,000 and more.

When it comes to flat pack extensions, a basic one is anticipated to cost £750 to £1,440, a mid-range is predicted to cost £1,275 to £1,800 and a luxury flat pack addition is estimated to cost between £1,650 to £3,600. Please note that the figures mentioned above are for building the shell of the addition alone.

The estimates do not include the cost of any fittings and fixtures, as they are totally of your own decision. However, our estimations do incorporate VAT. This is because the great majority of builders who undertake additions are VAT registered. Otherwise, they would only be able to finish one or two projects each year before meeting the government’s VAT registration requirement.

  • On average, a 30 square metre single-storey expansion constructed on a budget costs between £30,000 to £48,000.
  • If your funds can stretch a bit more, a mid-range expansion of this size normally costs between £51,000 and £60,000.
  • These prices exclude fitting charges.
  • The price per square meter isn’t considerably greater if you want to build a two-story addition.

Builders often give estimates based on square meters rather than floors. The primary additional expenditures you’ll need to take into account are scaffolding, extra material for the floor joists and walls, heating, plumbing, and electrics, as well as whatever fittings you want.

Both single-storey and two-storey additions require foundations and a roof. Depending on your budget, a 40 square meter, two-storey addition will typically cost between £48,000 and £76,000, or between £80,000 and £88,000 if you have more leeway in your spending plan. For a mid-range development or a budget project, a two-storey expansion of 60 square meters normally costs between £120,000 and £132,000 in total.

The location of your home is also crucial. Your addition will probably cost more if you reside close to London. A glass addition will cost between £1,350 and £1,950 per square meter for a budget finish, between £1,800 and £2,300 for a midrange finish, and above £3,000 per square meter for a premium finish.

  • Budget for 10 to 12 weeks of labor for a normal extension.
  • The cost of a flat pack addition ranges from £750 to £1,140 per square meter for a cheap choice, £1,275 to £1,800 for a midrange option, and £1,650 to £3,600 for a luxury option.
  • The building process takes just 1 to 2 weeks, as you can guess from the name.

When you consider adding a kitchen or bathroom, things become a little more challenging. Plumbing must be considered when granting planning approval, and then it must be installed. It’s wise to perform this correctly to guarantee that your extension is secure and durable.

  • You’ll need to budget an additional £5,000 to put a bathroom in your expansion.
  • The bathroom suite and finishes you pick will affect these prices, though.
  • A kitchen will set you back more money than a bathroom; for a low- to mid-range kitchen, your bill will increase by about £10,000.
  • You must include in the price of any fittings in addition to the expenditures of building the extension’s shell.

If you’re on a strict budget and developing a 20-square-meter kitchen expansion, you should budget an additional £2,600 to £6,200 on top of the building expenditures (including labour, but excluding appliances). If your budget is larger, you might add an additional £5,600 to £12,000 to the extension’s price (including labour, but excluding appliances).

  1. Bathroom additions are often modest.
  2. For a high-end finish, the typical price to install a new bathroom suite is between £2,750 and £7,000.
  3. Are you prepared to begin building your home addition? You can locate the best builders with the aid of HouseholdQuotes.
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Is it less expensive to construct an addition over a garage?

We’ll examine the average price of an addition over the garage in this section. As the framework and foundations are already in place, it might frequently end up being less expensive than starting from scratch to create an expansion. Although it won’t provide you much more room, an addition over a single garage may nevertheless be quite helpful.