How Much Does A Kitchen Extension Cost In UK | 2023 Expenses

“Why not add a small kitchen extension” is probably the first thing that comes to our mind whenever we want to upgrade our kitchen. Well, it’s practical, and you end up with more cooking space. But what about the cost of this whole process?

It’s better to search for an average cost of kitchen extensions before rushing toward the construction work. 

Well, here is your quick answer:

Adding a small kitchen extension to your property will cost you around £12,000 for construction and interior. While you may end up spending over £45,000 to £60,000. 

On average, homeowners are expected to pay £1200 to £1700 per square meter. You can save some money if you can do DIY work by yourself.

There are several types and kitchen extension ideas. And the cost varies depending on the type. So, sit back and hook on reading for your detailed information.

Average Cost Of Kitchen Extension UK

The rule of thumb is that the more you customize your extension layout, the more you are expected to pay. Have a quick look at the average price:

Types Of Kitchen ExtensionAverage Cost
Rear£12,000 – £15,000
Side Return£25,000 – £35,000
Wrap Around£16,000 – £22,000
Double Storey£40,000 – £60,000
Dormer £25,000 – £45,000
Conservatory £15,000 – £25,000
Glass£18,000 – £50,000
Orangery £15,000 – £18,000
  • The rear and Conservatory are mostly picked for small homes. Also, these cost a bit less compared to all other types.
  • Many Brits opt for orangery extension due to its aesthetics and natural sunlight.

Kitchen Extension Cost Calculator

Truth to tell, it can be a bit confusing for homeowners to decide which option is best for them. That’s why it is best to decide your budget first and then customize your cooking zone plan.

3 Metre Kitchen Extension


Undoubtedly, it is the most famous type as it requires less construction work. It can be done within 4 to 6 weeks. The plus point is you can also pick a glass ceiling with it.

It is worth mentioning that adding a glass interior will be more expensive rather than simple French or Shaker doors. 

Do you need planning permission for a 3-meter extension?

No, you don’t need planning permission to add a 3-meter extension to your property.

Rear Kitchen Extension Cost

Normally, you can add a 4m rear extension.

Let’s suppose that you are planning to keep things low-key, in such a case; you need a total budget of £15000.

You’ll be spending most of the money (around 75%) on labour and building costs.

Rear-Kitchen Extension Cost

You won’t need to add a separate door or any window, but interior and decor enhancement may come with a separate £500 to £1000.

Conservatory Kitchen Extension Cost


Conservatory extension is a great way to connect indoor and outdoor sections of your home. You’ll need wood, insulated stud work and roof glass. 

All these essentials mainly cost anywhere from £7000 to £10,000.

You can cut the cost by opting for a regular roof rather than insulated glass. Generally, it takes 4 to 6 weeks to complete the work. You are expected to pay an additional £6000 in labour costs.

Side Return Kitchen Extension Cost

It is going to be an expensive one.

A narrow side return extension can cost around £25,000, while for a Victorian style, you need a budget of £35,000.

This can be even more expensive in big cities as the labor cost is much higher there.


On average, a typical brick-side return extension will cost you £2500 per square meter.

Glass Kitchen Extension Cost

Modern glass home extensions are both beautiful and expensive.


Typically, these are used to link the home and garage, but now there is a huge buzz about adding them as additional diner space.

A small glazed glass extension can cost £15,000.

Adding it is relatively easy rather to the typical brick style, and the whole construction work mainly takes 3 to 5 days.

Do glass box extensions need foundations?

No, ground foundations and planning permission are not essentially required to add a glass box extension to your home.

Terraced House Kitchen Extension Cost

This style is best for semi-detached homes and mainly resembles the rear kitchen extension. Adding it will cost you anywhere between £15,000 to £20,000.

Terraced-House-Kitchen Extension Cost

Typically, it is added toward the rear garden side in a traditional brick style. You are expected to pay around £2000 more if you opt for modern kitchen wall decor.

Double Storey Extension Cost


A double-storey kitchen extension is the most expensive one. It requires a lot of paperwork and planning permission. Typically, it takes 8 weeks and around £50,000 to add a double-storey kitchen extension.

To cut the expense, many homeowners and planners go for flat roofs, which weaken the structure over time. On average, you are expected to pay £4000 per square meter for this idea.

Orangery Kitchen Extension Cost

An orangery is rather a style rather than a full-fledged extension.

Still, to this day, it is considered the best way to add tons of natural light to your space. It is mostly combined with a rear extension for extra space.

The whole ceiling of a specific area is replaced with insulated glass.

Orangery-Kitchen-Kitchen Extension Cost

Usually, this area is 3 meters. Be ready to spend £15000 if you want to add an orangery to your space.

5 Factors Deciding The Kitchen Extension Cost

Mainly, there are 5 major factors that can add to or reduce your expenses. Have a quick look at them below:

1. Size Of Your Kitchen Extension

The rule of thumb is that a small extension costs less than a 5 or 10-metre extension. Also, you end up paying more as a “labour cost” if you opt for a bespoke or modern style.

2. Styling And Decor

Nobody wants a mismatched cooking zone. So, if your cooking area is already made of expensive material and has an expensive finish, you may spend £5000 more just to match the previous style.

3. Specifications And Permission

If you’re planning to add a glass or double-storey extension, you need to have permission and follow specific material requirements. This can add more expense and take long compared to a small extension.

4. Your Location

This may surprise you, but on average, homeowners from big cities end up paying £3000 more. In Central London, such services are more expensive.

5. Your DIY Skills

This is the best way to cut labour costs. If you can do the wall paint or the electrician work, you can save around 13% to 15% of your total budget.

Kitchen Extension Cost

Cost Of Building A Kitchen Extension FAQs

How much does a kitchen extension cost?

A lowkey small kitchen extension cost around £15000 to £17000. But a glass-glazed customised extension can cost you over £50000. Typically, you’re expected to spend £1500 to £3000 per square meter.

What size extension can You build without planning permission?

You can extend your home by 4m only without permission. Anything over that, regardless of the extension type, requires prior approval from authorities.

How much does a brick extension cost?

Using brick is cheap and practical. You’ll need a budget of £10,000 to £15,000 to add a 3-meter brick extension to your property.

Are glass extensions cheaper than brick?

No, glass extensions are more expensive than brick. You need a budget of £2000 to £2200 per square meter for glass, while £1500 to £1700 if you opt for bricks.

Wrapping It Up!

Adding a kitchen extension is the best way to increase your home value by up to 13% more. Also, it improves the aesthetics of your property and provides additional space.

Planning an extension can be difficult as several factors can add up to its cost. Typically, for a small 3-meter kitchen or home extension, you need to have a budget of £15000.

Spare a few bucks for miscellaneous changes, and it is best to consult the authorities first if you want to add a double-storey or over 4-meter extension.

We hope that this article helps you to understand the average cost depending on the types. Well, in the meantime, be happy and keep on living your dreams!

I like to research and write about modern kitchen designs and kitchen appliances; Whether you are looking to design a perfect kitchen or want the best cooking experience, my writing will surely help you out!