How to plan a functional kitchen: zones, work triangle, ergonomics

A functional kitchen starts with zones, not with furniture. Split it into five work zones and keep things where you use them. It's the oldest and best-proven rule in kitchen design, and its roots go back to work-efficiency studies from the 1920s.

The sentence I hear most often is: if only I'd known earlier. The good news is that a kitchen doesn't have to be designed by instinct. There are proven rules that work regardless of the square footage.

Start with five work zones

Modern kitchen design is built around five zones. This approach, promoted among others by NKBA, organizes the kitchen around the sequence of tasks, so you don't run from one end to the other. The five zones are:

• stock: fridge, pantry, dry goods,
• storage: dishes, pots, containers,
• washing: sink, dishwasher, bins, cleaning products,
• preparation: worktop, knives, boards, spices,
• cooking: hob, oven, extractor.

The rule is simple. A thing should live in the zone where you use it. Spices by the hob, boards and knives by the worktop, containers near the prep zone. It sounds obvious, and yet in most kitchens it isn't the case.

The work triangle: sink, hob, fridge

The work triangle connects the three most-used points: the sink, the hob and the fridge. Per NKBA guidelines each leg of the triangle should be about 1.2 to 2.7 m, and the sum of all legs shouldn't exceed roughly 8 m. The point is to keep cooking from turning into a marathon.

The second rule. The household's main traffic shouldn't cut through the triangle. If the kids cross your path between the hob and the sink, the kitchen will tire you, even if it looks beautiful.

The comfort zone: what goes at which height

Not every spot in a cabinet is equally convenient. Research on height ergonomics shows that the most accessible area is the comfort zone between knees and shoulders, roughly 80 to 110 cm. Above about 170 cm accessibility drops sharply.

The practical takeaway. Keep what you use daily in the comfort zone. High shelves are for what you reach for on rare occasions. Don't plan heavy items above shoulder height, because that's a straight route to a strained back.

Before you pick furniture, walk the design zone by zone

Only once you have zones and a triangle does it make sense to talk about hardware. That's when you decide where to put cargo pull-outs, drawers or shelves, and catch mistakes before they're built. The cheapest way to do it is at the design stage, as part of a functional interior audit.

Frequently asked questions

Where do I start planning a kitchen?

With a split into five work zones: stock, storage, washing, preparation and cooking. Plan things where you use them. Only then choose the furniture and hardware.

What is the work triangle?

It's the line connecting the sink, the hob and the fridge. Per NKBA guidelines each leg should be about 1.2 to 2.7 m, and the sum shouldn't exceed roughly 8 m. The point is to keep the most frequent movements short.

At what height should I keep everyday items?

In the comfort zone, between knees and shoulders, roughly 80 to 110 cm. Above 170 cm accessibility drops sharply, so leave rarely-used items there.

How do I plan a small kitchen?

In a small kitchen, stick to zones and the comfort zone even more closely, because every movement counts. Favor deep drawers over shelves, so you can see and reach from above.

When should I plan the kitchen layout?

At the design stage, before the carpenter starts the fit-out. Then changing a zone or a piece of hardware is a correction on the drawing, not an expensive rebuild.

Sources

NKBA design guidelines (work triangle, zones) · Height-accessibility ergonomics (Prekrat et al.). The work triangle originates from Lillian Gilbreth's kitchen ergonomics studies (1920s). Examples come from audits run by the author.

This article is part of the guide Space organization before a renovation, where I gather everything worth thinking through before the work begins.