If you love where you live, stay put and rework the space with these kitchen extension ideas.

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Image: Traditional windows and doors, painted pine wall cladding and ceiling boards give this kitchen extension in a west London conservation area the look of a New England beach house. Kitchens by Holloways

Transform your home and create a well-planned and spacious layout by adding a kitchen extension. A single-storey addition is a lower-cost option but if your budget and local planning policy allows, go for two-storeys. Doubling the height won’t double the cost, as the foundations and roof will be factored in to the overall cost of the project, whether on one level or two.

Staying within the rules

Some kitchen extensions can be carried out under permi­tted development (PD) rules, which means that applying for planning permission is not necessary. There are plenty of kitchen extension ideas that work well withing these limitations. To see the legislation in full, visit the Planning Portal. ‘You can apply for PD if your extension, including previous extensions or other buildings such as sheds, does not exceed 50 per cent of the total area of land around the original house,’ says Ana Martins of architect Martins Camisuli.

Read more: A guide to Permitted Development Rights

Seeking planning approval

Planning permission for your kitchen extension may be needed, and if your property is in a conservation area or is listed, further restrictions will apply. ‘We believe in submitt­ing an application for what you actually want, within reason, and seeing how the planners react,’ says Ana.

‘Planners are always open to discussions and are usually reasonable, unless your proposal is way beyond what is acceptable. Approach your neighbours to see what they might object to. They have a lot of power; an objection could destroy your plans.’ Bear in mind that party wall agreements may be required if work affects the boundary with neighbouring properties. All projects are subject to building regulations consent.

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Image: A conservatory was demolished to make way for a sizeable new kitchen extension for this 1930s house in Kent. Kitchen by Martin Moore

Structural considerations

As well as traditional masonry construction, alternative methods are worth considering, such as SIPS (structurally insulated panels), which are quick to build with. Whichever method you choose, the kitchen extension can be clad in any finish you want, from brick to render or metal. Improving the connection between the inside and outside space will certainly improve the way you enjoy your home, so the arrangement of windows and doors is key to the project’s success.

Read more: Exterior cladding: which material to choose for your home

Sliding glass doors provide wide expanses of glass and slimline frames maximise views to the garden. ‘A three-panel set can be two-thirds open, not quite as good as the full opening that bi-folds provide, but they look far more elegant when closed,’ says Charles Barclay of Charles Barclay Architects.

Single storey extensions

With single-storey kitchen additions, rooflights are recommended for bringing light into the kitchen as well as the centre of the house. ‘Use them sparingly and strategically, working to highlight the architecture rather than flooding the space with light indiscriminately,’ advises Charles. Roof lights come in all sorts of configurations, traditional raised lanterns are another option, while structural glazing can make a real style statement.

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Image: By filling in the side return and extending into the garden, a generous kitchen extension was created for this home. Project by Martins Camisuli

Where to eat in your extension?

Even if you don’t intend to use the space for formal dining, a large table provides a space for snacking, cha­tting or homework. Thinking about getting food from the kitchen to the dining table helps when considering the position of furniture and kitchen units. In an open-plan space, an island will divide the room naturally; just zone the dining area with a table, rug and sideboard. In a broken-plan scheme, include glazed or pocket doors for the flexibility of opening up the rooms for a party.

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Image: A copper-clad kitchen extension makes the most of limited external space. The glazing and lighting were designed to let the inside borrow space visually from the garden of this Victorian house. Project by UV Architects

Order of works

Keep your kitchen extension project on schedule with this useful timeline: 

WEEK 1-3
Consult with your architect or designer about the plans for your extension. They will put together a budget and fee proposal for the work so that preliminary drawings can be produced.

WEEK 4-7
Once the preliminary design is finalised, detailed drawings can be created.

WEEK 8-15
If your project requires planning consent, your application will be submitted to the local council’s planning department.

If your scheme is approved following the eight-week consultation process, you can then put the project out to tender.

Once you’ve selected a builder, work can start on site. Construction usually takes between three and six months, depending on the size and complexity of your project. You can use this time to source internal materials and products. Note that many kitchens often come with a lead time, so plan ahead.

WEEK 21-22

WEEK 23-24
Building the structure up to dampproof course and sub-structure put into place.

WEEK 25-26
Construction of walls, external and internal.

WEEK 27-29
Roof structure to be built and finished with your chosen roof covering.

Windows and doors fitted.

First fix of electrics, plumbing and carpentry.

Plastering and allowance for drying time.

Second fix of electrics, plumbing and flooring. Kitchen cabinets and appliances installed.

Final elements of decorating to be completed.

Snagging inspection. This is a walk through of the extension with your contractor to identify any minor faults or errors so they can be resolved as quickly as possible.


For more ideas on kitchen design, or for up-to-date advice on renovating and extending your home, read Grand Designs magazine digitally for free now by registering your details



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Kitchen extension ideas to improve your home

If you're considering a kitchen extension, this handy guide takes you from planning and design ideas through to a detailed timeline for your project.