Kitchen Islands Explained: Layout, Space and Planning Considerations
In short
A kitchen island is a freestanding run of units in the middle of a kitchen, open on all sides, that adds worktop, storage and often seating. It can also hold a hob, sink or appliances. It works best where there is enough clear space around it to move and open doors comfortably.
A kitchen island is the centrepiece of most open plan kitchens. Standing apart from the wall units, it gives extra worktop and storage, a place for family and guests to sit, and a natural divide between cooking and living. Islands look effortless when they are planned well and awkward when they are squeezed in, so the planning matters as much as the design.
How much space you need
The most important measurement is the clear walkway around the island. As a working guide:
- Around 1,000 to 1,200 mm between the island and the facing units is comfortable for one or two cooks and lets appliance doors open fully.
- Less than about 900 mm starts to feel tight, especially opposite an oven or dishwasher.
- Allow more where seating backs onto a walkway.
An island also needs to be in proportion. A long, narrow island often works better in a London side return or rear extension than a deep square one.
What to put in the island
- Prep and social only: the simplest option, with clear worktop, storage and seating.
- Sink: lets you face the room while preparing food; needs water and waste routed through the floor.
- Hob: a sociable layout that needs extraction, either a ceiling extractor, a downdraft unit or a hood above.
- Appliances: wine fridge, dishwasher drawer or microwave drawer.
- Seating overhang: typically 250 to 300 mm deep for comfortable knees, with supports if the overhang is long.
Services to plan before first fix
An island in the middle of a room has no wall to hide services in, so everything must come up through the floor. Before first fix, decide on:
- Power for sockets (pop up or side mounted) and appliances
- Water and waste for a sink, with enough fall in the floor void or screed
- Ducting for downdraft or recirculating extraction
- Pendant positions above the island, centred on the finished worktop
- Underfloor heating layout, so loops avoid the island footprint
On a concrete slab in a new extension, waste routes must be set before the floor is poured. That is why an island layout should be fixed early in the design.
When an island is not the answer
If the walkway would be under about 900 mm, a peninsula (attached at one end) or a generous breakfast bar often gives the same benefits without blocking movement.
How we handle kitchen islands on London’s Prestige projects
We set out island positions on site against the real room, confirm walkways, and plan services, extraction, lighting and heating together before first fix, so the island sits exactly where it should. Your project manager coordinates the kitchen supplier, electrician, plumber and floor layers through one programme. Our Richmond Hill extension shows an island built into a bright, open plan family kitchen. See our kitchen renovation service or read our guide to kitchen renovation timelines and budgets, then arrange a site visit to plan yours.
Common questions
What is the minimum room size for a kitchen island?
It depends on the island size, but you need roughly 1,000 mm of clear space on each working side. Many designers suggest a kitchen of at least around 4 metres wide for a comfortable island.
Can I put a sink in a kitchen island?
Yes. Water and waste are run through the floor, which is easiest during an extension or full kitchen renovation when floors are open.
How much overhang do I need for seating?
Around 250 to 300 mm is typical for comfortable seating on bar stools. Longer overhangs may need hidden supports, depending on the worktop material.