Stunning kitchen extension ideas — get the perfect design

bright kitchen extension with rooflight and exposed brick
(Image credit: Chris Snook)

Our collection of brilliant kitchen extension ideas will give prospective projects food for thought and plenty of design inspiration. No matter what stage your project is at, these ideas of all shapes sizes and budget (including before and after galleries) are both achievable and show-stopping. 

One of the most popular reasons for building an extension, creating a bigger kitchen space is a great way to curate a new hub of the family home. 

From small side returns on a terrace houses to full-width rear extensions on semi-detached properties, kitchen extensions offer the chance to rearrange a layout which doesn't quite work for your lifestyle and can give a tired home a new lease of life. 

We've included before and after pics of real project where possible, alongside project information and a range of expert advice from architects and kitchen designers alike. 

Use kitchen extension ideas to create a design brief for your suppliers and architect

Whether you're working with an architect, designer or doing the planning on a DIY basis, hunt around to find kitchen ideas, designs and styles that inspire you. Analysing how your existing home isn't fulfilling expectations or requirements is also fantastic starting point to work out a priority list and design brief, as well as focusing your inspiration.  

"The first question we ask a client is 'why are you undertaking this project?'", explains Helena Myers, director of The Myers Touch Design Studio. "It'll really get you thinking about what it is you want and will help you and the designer to begin exploring what outcome you hope a new kitchen space will bring."

Try to consider what the new kitchen space will be used for. Kitchens are rarely used simply to cook in anymore, so considering family seating, a small home office space or a children's play area will help kick start the layout. 

Design an appropriately sized kitchen extension

Kitchen extensions don't have to be huge, sprawling designs to transform an existing house. "Don't always assume that the only way to get what you want for your home is the widest, longest extension you can achieve under planning permission or Permitted Development," advises Laura Jane Clark, director of Lamp Architects

"Often a big square extension can result in a dark cavernous home that will need extensive rooflights, windows and additional lighting. As cost-saving alternative, think about clever ways to use your design that will minimise the need for a huge extension."

By utilising large glazing and window styles and other small kitchen extension ideas, a greater connection with the garden can be established and the sense of space will be increased. 

Bifold or sliding patio doors are fantastic options that offer views out all year round, while installing a large roof lantern can bring in plenty of natural light to the new space.  

Be realistic about kitchen extension costs

modern kitchen diner extension with wooden flooring and picture window

(Image credit: Jeremy Phillips)

One of the biggest pitfalls of a project is not being realistic about the questions 'how much does an extension cost?'. Aspiring extenders might be surprise in particular by how much materials and labour shortages have inflated costs in recent years and their budget now seems a bit tighter than it was previously.

On the whole, a kitchen extension will cost around £1,500- £2,250m2. Naturally this will depend on the quality of construction and the level of detailing. For instance, using off-the-shelf sizes for patio doors and a kitchen design from IKEA will massively reduce costs compared with bespoke glazing and made-to-measure units. 

That being said, a kitchen extension is an investment and will be used every day by at least one member of the household. Taking time to figure out a decent budget for your inspiration (and how much it might add value to your home), will set you on the right path.

Plan an open plan kitchen, living and dining extension carefully

white rendered kitchen extension with pitched roof

(Image credit: Juliet Murphy)

Open plan has long dominated kitchen extension layout designs, and for good reason, but be sure to take the time to organise the space from the early planning stages. 

For ideas on how to design a combined kitchen, diner and family room – from circulation spaces to buying appliances – take a look at our guide to open plan kitchens

This 1930s semi was extended by Iguana Architects. The new space is inspired by biophilic design, with a butterfly roof pitch and green roof covering.

Let in the light with an orangery kitchen extension

small kitchen extension with orangery style roof lantern

(Image credit: Vale Garden Houses)

When designing a kitchen extension, spend time and effort on making sure plenty natural light infiltrates the space — but don't make the rest of the house feel dark! This is a delicate balance, but one that is important to get right. 

Find inspiration from kitchen conservatory extensions in how to incorporate rooflight, roof lanterns and patio doors into the new space. 

Although beware of the Building Regs rule that states that the area of windows, roof windows and glazed doors mustn't account for more than 25% of the extension's floor area. 

"The reason for this restriction is simply down to thermal efficiency," explains chartered surveyor Ian Rock. "If you want large amounts of glazing, one solution is to demonstrate that the overall heat loss of your extension with the increased area of glass will be no worse than if you'd stick to the 25% rule." 

Transform a galley kitchen with an L-shaped wrap-around extension

galley kitchen with island in kitchen extension

(Image credit: LochAnna Kitchens)

Open up a dark and pokey galley kitchen with a wrap around extension. Extending out to the rear and side will not only increase a home's value, but rearranging the existing rooms to suit an open plan lifestyle will also make the layout flow more easily. 

The new steel beams of this extension reveal the previous layout of the existing home. Cleverly the galley kitchen has ben opened up with a wrap-around extension that provides a new dining space and seating area. 

Look to the back of a semi-detached house

Creating much-needed space with a rear kitchen extension can transform a semi detached home. It's not often this style of homes is organised to make the most of garden views or to house a large, open-plan cooking area so extending to the back can unlock their potential.

Be sure to consider the roof line when looking at rear extension ideas. A flat roof, like the one above, might allow you to maximise ceiling height without blocking out first floor windows. 

Alternatively, create a vaulted ceiling extension with a pitched roof for a truly special addition to an existing house. 

Transform a dated bungalow with a kitchen extension

white modern kitchen diner extension with vaulted ceiling

(Image credit: Siobhan Doran)

While bungalow are often derided for being dated and perceived as unsuitable for families, they usually have a large garden plot making them a great proponent for a kitchen extension to reinvigorate the layout. 

Play with different scales in ceiling heights and pitches, emphasise an asymmetrical form or create a whole new character through a complete remodel. These properties can act as the perfect blank canvas for your kitchen extension ideas. 

Here, the mid-century aesthetics of the bungalow have been encouraged in the kitchen diner ideas, while the vaulted ceiling adds a new sense of drama. 

Bring new materials into a kitchen extension 

open plan kitchen and dining space with wood cladding

(Image credit: Richard Chivers)

Bring a new material into a kitchen extension using a tile splashback, a quirky worktop or internal timber cladding ideas. 

Previously suffering from low ceilings and a lack of natural light, the kitchen and dining space of this terrace has been reconfigured by Yard Architects, thanks to a single storey extension

Strip rooflights bring light into the new space while oak batten cladding lines the dining space and back wall of the kitchen, concealing the larder cupboard and fridge. 

Create a tailored layout for your kitchen extension

large rear brick extension with sliding doors and overhang

(Image credit: Jim Stephenson c/o nimtim Architects)

"The homeowners behind this extension project are Mediterranean and they wanted an outdoor covered are to sit and enjoy the garden," explains Allie Mckinnon, project runner for nimtim Architects

"The house is west facing at the rear and we designed the roof canopy to give shelter as well as reduce solar gain from the largely glazed extension. 

"We also added in opening rooflights to bring in additional light and to create air movement and ventilation through the space. For those extending, the aspect of your design is important to consider and we would suggest plotting the proposed scheme in-situ and noting how to sunlight affects this area throughout the day."

Choose the right roof type for your kitchen extension

Achieving the right roof type for a kitchen extension is an underestimated but incredible important detail that will affect the overall design, the cost and how to extension interacts with the original building. 

Pitched roof extensions offer the chance for vaulted ceilings or additional hidden storage, but be sure to match the angle or the existing house, or at least the styles of the surrounding areas, 

Flat roof extensions, on the other hand, can come alive with roof lanterns and other ceiling glazing. This style really makes a marked visual difference between the old and new, so leaning into a 'modern' kitchen looks incredible. 

Look to the side to increase space in a kitchen

glazed side extension to white rendered house

(Image credit: Richard Downer c/o Van Ellen Sheryn Architects)

Don't sacrifice valued garden space for your new extension and build to the side of the house instead. 

Side extension ideas can come in all shapes and sizes, but when installing a kitchen into the addition, be sure the flow from one end of the house to the other is seamless. 

A stone lean-to shed was replaced with a contemporary glass extension designed by van Ellen + Sheryn to extend the kitchen diner. A large glazed extension provides views out to the garden. 

Balance kitchen and living areas in an open plan space

modern open plan kitchen and living room in extension

(Image credit: David Barbour)

Kitchens are rarely just kitchens these days. There is often a dual functionality in modern kitchen ideas, be it for dining, watching tv, reading or home working. 

Think about how these spaces will interact with each other and, importantly, how you can encourage flow through the room. Map out how you will travel from the kitchen area to the sofa, or the dining area, through the back door and into the garden.

From this, aim to balance furniture placement with through-routes to save an awkward layout that is cumbersome to navigate. 

Pay attention to details when opening to the garden

kitchen extension with views of garden through bifold doors

(Image credit: Origin)

When installing bifold or sliding patio doors in a new extension, the devil is in the detail. The difference by high and low quality materials will be noticeable after years of use — make sure your choice is the right one. 

"A priority in this project was the threshold. The homeowners wanted to minimise the step from the inside to outside environments, while ensuring it remained watertight," explains Victoria Brocklesby, COO at Origin

"After getting in touch with Origin, they were put into contact with their local partner whose installer sunk the threshold into the floor which left a minimal step of just 14mm."

Combine old and new in a small cottage extension

glass extension to stone cottage kitchen

(Image credit: Simon Burt)

A lovely way to introduce a new extension into an older property is to let both influences really shine in their own right. Let interesting oak beams or stone walls contrast with large swathes of glazing and contemporary textures in your new addition. 

This will give personality and a sense of uniqueness to kitchens in cottage extensions— a social space usually classed as the hub of the home. If you don't celebrate a home's identity there, where else is better to do it? 

This granite stone cottage was beautifully extended using a small conservatory. The original inglenook stands proud (left of shot) against the new cast concrete island. 

Establish your favourite kitchen layouts — from islands to galleys

modern grey kitchen with island in modern extension

(Image credit: Dave Burton)

When starting from scratch in a kitchen extension it can be difficult to create a new layout with a blank canvas. We're so used to making do with awkward or idiosyncratic spaces in our homes that when faces with a blank box to do with what we like we get overwhelmed. 

Research the different types of kitchen layout ideas and try to remember times when you have interacted with each of them. Perhaps your childhood home has a large central island where the family gathered and you'd like to recreate it. Or, is there a galley kitchen in a friend's house that you love and would like to emulate the convenience? Likewise, do you hate single line kitchens of holiday lets and know for sure that';s not for you? 

Use these real-life examples to inform size, shape and proportions. 

Create drama in a new kitchen extension

large kitchen extension to brick barn with mezzanine space

(Image credit: Future)

Going up two stories, rather than just the one gives opportunity for a sense of architectural drama and the ability to create and connect other spaces. 

Double storey extensions won't cost much more per square metre than single storey and can (in some cases) still fall under permitted development. 

In this extension to an old storage barn, the homeowners used their two storey extension to create a reading nook above their living space on the mezzanine while a bridge landing leads to the bedrooms. 

Give lighting it's time to shine

black and white traditional kitchen with gold lighting and ladder

(Image credit: Armac Martin)

The joy of a kitchen extension is that you get to plan and tailor every specific element of your new space. And this should definitely include the lighting scheme. 

While a grid of downlights is cheap and somewhat easy to fall back on, this will not fulfil all of the lighting requirements for a kitchen. Play with kitchen lighting ideas like wall lights near open shelving, pendant lights over an island, LED strips under cupboards and so on. 

The effect of a good lighting scheme in a new kitchen is undeniable. Make sure yours uses the best kitchen lighting you can afford — it will make all the difference. 

Choose a flooring create a cohesive space

white modern kitchen extension with rooflight and island

(Image credit: Gabriell James Chairmakers)

You might choose to completely separate the new kitchen extension from the rest of the house, but one stylish trick is to install the same kitchen flooring ideas in the spaces leading to the new extension. 

Subtly linking together the two spaces will create a more cohesive overall home, without making the old rooms feel tired or underloved. 

That being said, kitchens require a certain hardiness in their flooring, so try to choose something that will work for high traffic areas, such as solid or engineered wood, as well as those near water spillages, like LVT or porcelain tile. 

Keep sustainability in mind when adding a new kitchen

second hand kitchen in new extension

(Image credit: Used Kitchen Exchange)

While a brand new kitchen bespoke to the space and your lifestyle is extremely tempting during a project, considering a second hand kitchen is an amazing way to cut-costs or get a higher-quality finish for less. 

This beautiful walnut kitchen in an orangery-inspired extension was originally priced at £60,000 and designed for another family home. The new owner bought it from the Used Kitchen Exchange for just £9,000 complete with Miele appliances. 

Use cladding to make a kitchen extension stand out

A new extension is not just an opportunity to transform interior spaces, but also to give the exterior of a tired or dated home a refresh and regeneration. 

Opting for interesting house cladding choices can take an extension from being a square box to a stunning new space with wow-factor. 

This terrace kitchen extension used corten steel to complement the shades within the original Victorian brickwork. 

Use a side return to create a new terrace kitchen extension

Utilising the wasted space to the side of a terrace house is one of the most popular extension designs. Essentially doubling the size of the kitchen space, often a dining or sitting area is created. 

This home's glass extension to the side of the previous galley kitchen has opened up the space to suit a dining area with roof lights above. 

How Can I Extend my Kitchen Area?

"The input of an experienced designer will really help stitch the old with the new," says Deputy Editor Michelle Guy. "They will ideally consider how the new space flows and connected with the existing house, whether to opt for a contemporary extension or something that blends with the existing house, and the size and scale of the extension — often referred to as 'massing'.

Your extension will need to comply with the Building Regulations and inspected at different stage of the build. If your extension involves a boundary wall, you will need to comply with the Party Wall Act (and serve a Party Wall Notice to adjoining neighbours). 

Do I Need Planning Permission for a Kitchen Extension?

If a single-storey extension plan is less than 8m in depth from the rear of the existing house, you do not need planning permission for a kitchen extension, as this would fall under Permitted Development (PD) rights.

"These PD rights are set out fairly clearly in government guidance on the planning system — detailed rules are found within 'Permitted Development rights for householders: technical guidance' which is available on," advises planning consultant Ken Dijksman. 

"Understanding PD rights can be really helpful if you make a planning application for something that is just a little larger than PD allows," he continues. "This is because the council is duty-bound to compare what you want with what you can do anyway.

"If PD would allow you a certain size of extension and what you want to build is a few metres higher or longer, remember that the council can only actually assess the impact of those additional elements. The fall back is your PD, and they cannot prevent that, so it's only the additional amount that they can legitimately object to."

Amy Reeves

Assistant Editor Amy began working for Homebuilding & Renovating in 2018. She has an interest in sustainable building methods and always has her eye on the latest design ideas. Amy has interviewed countless self builders, renovators and extenders about their experiences for Homebuilding & Renovating magazine. She is currently renovating a mid-century home, together with her partner, on a DIY basis, and has recently fitted her own kitchen.