How to design & plan your dream kitchen extension

How to design & plan your dream kitchen extension

The kitchen reigns supreme as one of our top home improvements projects with many homeowners yearning for a big open-plan space to cook and socialise in. If you don’t want to move to get one, then a kitchen extension could be for you. As well as adding extra space, it can really boost the value of your home.

A kitchen extension is a big job though and it makes sense to follow a few steps to keep your project running smoothly and your stress levels low. Read on to learn how to plan your extension and create a perfect space.


The more planning you do, the smoother your project will run. It may sound obvious, but don’t be tempted to start work before you’ve thought through every last detail. Work out the size and layout of your extension first and consider what you want from your new space. Do you need a kitchen/diner? Do you want to use the space for entertaining or relaxing? Do you need access to other rooms or the garden?

Natural light

You don’t want your new space to be dark and gloomy, so make sure you take full advantage of all natural light sources. For windows and doors, plan where they will go and make them as big as possible to draw light in. Bi-folding and sliding doors are popular choices.

Don’t forget that you can also light from above with glass roofing, such as a roof lantern or rooflight. Roof glazing not only looks fantastic, it also brings in a whopping 40% more light than vertical glazing.

Find an architect

Next, you’ll need to look for an architect or designer who can guide you through planning and help to bring your ideas to life. Try to find a designer through recommendation from someone you know and have a look at some projects they’ve done.

Make sure your architect is RIBA Chartered too. You can check out their official directory of accredited architects by visiting:


Your architect will be able to draw up some budget costs for you. Expect to pay between £1300 and £2200 per square metre for your extension, depending on the quality of your fittings. It’s also wise to build in a contingency of around 10% to cover any unforeseen costs.

Building Regulations and planning permission You’ll need to check if your plans come under permitted development or if you need to apply for planning permission. It can take up to 10 weeks for planning permission to be granted, so factor in plenty of time to cover this.

For more information on planning permission and Building Regulations, visit – and

Single storey extensions are the most likely types of projects to be approved under permitted development. Don’t forget that you’ll still need to obtain Building Regulations approval though. If you’re using an architect or a specialist company to help with your project, they’ll guide you through this process.

Choose your builder

It’s a good idea to spend some time researching builders and asking friends and family for recommendations. Costs can vary for building works, so it’s worth asking for at least three quotes for comparison. When you’ve decided on your builder, ask them to draw up a proposed schedule of works.

Payments are usually scheduled based on the completion of specific elements of the build and you’ll probably be asked for a deposit before work starts. Never pay the full cost of the building work before starting your project

Speak to kitchen designers

Now comes the exciting part when you can start planning your dream kitchen. Your architect may have already planned the basic layout of your kitchen, but now you can finalise the design with a specialist kitchen designer. They will be full of knowledge on the latest products, fixtures and fittings and their experience will give you lots of ideas.

At this stage, say where your electrical and plumbing services will be positioned. You’ll also need to confirm the location and size of windows and doors.

The work!

You’ve got through all the planning stages and now the building work begins. There are two stages in building – ‘first fix’ where you start work on walls, floors, plumbing and electrics and the ‘second fix’ where they are all completed, usually after plastering.

When the building work is done, you’ll need to deal with any snagging issues relating to the finish. Be thorough – it can be tricky to get people back to fix things after the final payment has been made. You should only make your final payment to your builder when you’re satisfied. At this stage, he should provide you with a final certificate to cover his work.

Now you’re at the final stages of laying flooring, installing kitchen cabinetry, painting the walls and fitting your worktops. Once they’re in place, it’s time to pop open a bottle and toast your lovely new kitchen extension!