Single vs Double Kitchen Sinks: Which Option Is More Functional?

The Short Answer

American articles talk about single and double sinks as if those were the only two choices. In UK kitchens there are really three, and the one in the middle is the one most British homes have had for decades:

• Single bowl: one basin, from compact to very large.
• One and a half bowl: one main basin plus a small second bowl, usually with a drainer.
• Double bowl: two full-size basins side by side.

The right one depends less on fashion and more on three plain questions. Do you own a dishwasher? What is the biggest thing you wash by hand? And how wide a base unit can you give up to the sink? Answer those and the choice more or less makes itself.

The Three Types Side By Side

	Single bowl	One and a half bowl	Double bowl
Best for	Homes with a dishwasher, big pans	Mixed hand washing and dishwasher	Daily hand washing, keen cooks, big families
Typical base unit	500mm or 600mm	Usually 600mm	Usually 800mm or wider
Fits an oven tray flat	Often, if the bowl is large	Rarely	Rarely, unless the bowls are very big
Wash and rinse at once	No	Partly	Yes
Worktop it uses up	Least	Middle	Most

Unit sizes vary from one sink model to another, so treat these as a guide. The sink's own fitting instructions state the smallest unit it will go into, and your designer checks that before anything is ordered.

Single Bowl Sinks

A single bowl gives you one uninterrupted space. That sounds like less, but it is the only style where a roasting tin, a wok, a stock pot or the shelf from the oven can lie flat under the water instead of being propped up at an angle and sprayed across the worktop.

If the dishwasher does your plates, glasses and cutlery, those awkward big items are most of what you wash by hand, which is why large single bowls have become so popular in new kitchens. The traditional Belfast sink, the deep white ceramic one you see in country kitchens, is a single bowl too.

The drawback is that the bowl can only do one job at a time. If it is full of soaking pans, you have nowhere to drain the pasta or rinse a cup. A washing-up bowl inside the sink, or a fitted colander or drainer tray that sits across the top, solves most of that for very little money.

One And A Half Bowl Sinks

This is the British compromise, and it is a good one. The main bowl does the washing. The half bowl takes everything else: tipping away the dregs of a mug while the main bowl is full of suds, draining vegetables, rinsing a cloth, defrosting something in cold water, or holding the cutlery.

It usually fits a standard 600mm base unit, so it does not cost you any extra cupboard space compared with a decent single bowl. Most come with a built-in drainer, and most can be fitted with the drainer on the left or the right to suit your layout.

The catch is that the main bowl is smaller than a true single bowl of the same overall width. If your biggest frying pan only just fits your current sink, check the main bowl dimensions of any one and a half bowl model carefully. Take the pan to the showroom if you need to. Nobody will mind.

Double Bowl Sinks

Two full bowls let you run a proper system: wash in one, rinse in the other, or keep one side for food preparation and one for dirty dishes. If you cook from scratch most nights, bake a lot, have a large family or simply do not own a dishwasher, this is the most functional sink you can have.

Some double bowls are split evenly. Others are offset, with one larger bowl and one slightly smaller one, which gives you a better chance of fitting big pans.

The price you pay is space. A double bowl normally needs a base unit of 800mm or more, and it takes a long bite out of the worktop. In a big kitchen that is no hardship. In a tenement galley or a compact new-build kitchen, that same 800mm might be your only good stretch of preparation space, and a sink is a poor trade for it. Our small kitchens guide covers how to protect worktop in a tight room.

Match The Sink To How You Live

A few honest questions will point you to the right bowl.

• Do you run the dishwasher daily? Go for a large single bowl, or a one and a half if you like somewhere to tip the tea.
• Do you wash up by hand after every meal? A one and a half or double bowl with a drainer will make that job quicker.
• Do you batch cook, bake or make jam? You need at least one bowl big enough for your largest pot. Measure it.
• Is there a utility room with its own sink? Then the kitchen sink can be smaller and neater, as the muddy boots and paint brushes go elsewhere.
• Is worktop tight? Choose the smaller sink and consider skipping the built-in drainer in favour of drainer grooves cut into a solid worktop, or a roll-up mat.

One thing you can ignore from American guides is the waste disposal unit. They are uncommon in Scottish homes, and you do not need to plan a bowl around one unless you particularly want it.

Inset, Undermount Or Belfast: What Your Worktop Allows

How the sink is fitted matters as much as how many bowls it has.

Inset sinks drop into a hole in the worktop and sit on top with a rim. They suit every worktop, including laminate, and they are the most affordable to fit.

Undermount sinks are fixed beneath the worktop so you can sweep crumbs straight in. They need a solid, waterproof worktop such as quartz, granite or a solid surface material. They are not suited to laminate, because the cut edge of the board would be exposed to water.

Belfast and other ceramic sit-on sinks rest on a specially built base unit with the worktop cut around them. They are heavy, so the unit has to be made for the job.

If you are keeping your existing units and only swapping a tired sink or worktop, the hole that is already there limits your options. Our kitchen repairs service can advise on what will fit.

What About The Material?

The number of bowls and the material are separate decisions, and nearly every material comes in all three layouts. Stainless steel is light, forgiving and the easiest to find as a one and a half bowl with drainer. Ceramic looks beautiful and resists stains, but it is heavy and less kind to a dropped glass. Composite granite sinks, like the black one at the top of this page, sit between the two.

We have covered that choice properly in a separate guide: stainless steel vs ceramic sinks. Read it alongside this one and you will have the whole decision covered.

Cost And Planning

Sink prices depend on material, brand and size far more than on bowl count, so we will not quote figures that would mislead you. As a rule, a bigger sink costs more than a smaller one in the same range, an undermount costs more to fit than an inset, and a wider sink unit means one fewer cupboard elsewhere.

In a full refit the sink is a small part of the total. Fitted kitchens from Ultimate Home Solutions start from £6,000, with most between £8,000 and £15,000, and finance is available from £35 a week, subject to status. See the finance page for details.

The real value of planning the sink early is that it sets the position of the dishwasher, the bin and the main preparation area. We draw every kitchen in 3D, so you can see exactly how much worktop is left either side of each sink option before you commit. Plumbing is handled by trusted installers, and all workmanship is guaranteed.

Quick Answers

Is a single or double sink better with a dishwasher?

A large single bowl. The dishwasher handles the everyday items, so what you need from the sink is room for the big pans and trays that will not go in the machine.

What size of unit does a one and a half bowl sink need?

Most are designed for a 600mm base unit, though some need more. Always check the minimum unit size stated for the model you like.

Are double bowl sinks old-fashioned?

No. They are less common than they were because dishwashers are now standard, but for a busy cook or a household that washes up by hand they are still the most practical option.

Can I fit an undermount sink in a laminate worktop?

It is not recommended. Undermounting leaves the cut edge of the worktop exposed to water, so it suits quartz, granite and solid surface worktops. Choose an inset sink for laminate.

Which way round should the drainer go?

Many people like the drainer on the side away from the hob and nearest the dishwasher, but the room usually decides. Most inset sinks are reversible, so you can choose at the design stage.