Metal Double Beds or Metal King Size Beds? How to Decide

Choose a metal double bed if your bedroom is average or compact in size, you sleep alone or share with a partner who does not mind closer quarters, and you want to keep floor space free for other furniture. Choose a metal king size bed if you share the bed nightly, either of you is tall, you have a restless sleeper or a child who joins you sometimes, and your room can take an extra 15 cm of width and 10 cm of length without blocking walkways. The decision usually comes down to two questions: how you sleep, and how much clear floor you can keep.

Our modern double metal beds UK range is a good place to start comparing designs, and our full bedroom furniture UK collection shows how each size fits into a complete room. Here is how to weigh up the decision.

The measurements side by side

A UK double mattress is 135 x 190 cm. A UK king is 150 x 200 cm. The frame adds a few centimetres on each side, though metal beds tend to add less than upholstered or timber designs.

That extra 15 cm of width means each person gains roughly 7.5 cm of personal space. The extra 10 cm of length gives taller sleepers more room so their feet do not reach the end of the mattress. These sound like small numbers, but on a bed you use every night, they often feel significant.

How you sleep matters most

Sleeping alone

A double gives a single adult ample room to stretch out. Unless you are very tall or simply enjoy space, a king is rarely necessary for one person.

Sharing with a partner

A double is the traditional choice for couples and works well for many. If either partner moves a lot in the night, sleeps hot or tends to wake when the other turns over, the extra width of a king can noticeably improve rest.

Tall sleepers

If either of you is tall, the extra 10 cm of length on a king is often the deciding factor. A double at 190 cm long can feel short for taller adults.

Children and pets

If a child regularly climbs in during the night or a pet shares the bed, a king makes the arrangement far more comfortable for everyone.

How much room your bedroom needs

The size of the room is the practical limit. Aim to keep around 60 to 70 cm of clear floor on each side of the bed if two people need access, plus enough space at the foot to walk past and open wardrobe doors or drawers.

In many UK homes, particularly terraced houses, new builds and flats, the main bedroom is comfortable for a double but tight for a king. A king in an undersized room can make the space feel crowded and leave bedside tables squeezed into corners.

The simplest test is to mark both sizes on the floor with masking tape. Walk around each outline, open the door and the wardrobe and see which leaves you comfortable.

What a metal frame adds to the decision

Metal beds have an advantage when space is close. Because steel tube is slim and strong, metal frames tend to sit tight to the mattress edge. A metal king may take up only slightly more floor than a chunky upholstered double.

Open headboards and raised legs also help a larger bed feel lighter. If you are leaning towards a king but worried about the room feeling full, a minimal metal frame with no footboard can make the difference.

Our king size metal beds UK sale include slim modern frames that keep the visual weight low.

Bedding, mattresses and accessories

Moving to a king means new bedding. Duvets, sheets and pillowcases need to match the larger size, and king bedding is widely available, though it is worth factoring into your plans.

The mattress is the most important part of either bed. On a king, couples often appreciate a mattress with good motion isolation, such as pocket sprung or memory foam, so one person’s movement disturbs the other less. Our mattresses UK range covers a variety of types and sizes.

Bedside tables should sit roughly level with the top of the mattress. On a king, slightly wider bedside surfaces can balance the larger bed visually.

Thinking about the future

If you are likely to move in the next few years, consider the rooms you may have later. A double fits almost any bedroom, while a king may not suit a smaller future home. On the other hand, if you are settled and your room comfortably takes a king, the extra space can make a lasting difference to how well you sleep. Our guide to UK king size bed dimensions and room planning gives more detail on frame and room measurements.

Metal beds are generally simple to dismantle and move, so either size is easier to take with you than a bulky upholstered frame.

Styling each size

A double metal bed suits a layered but restrained look. Two pillows, a couple of cushions and a throw at the foot are enough. Matching bedside cabinets on each side keep the arrangement balanced.

A king can carry more. A wider headboard gives room for additional pillows, and a bench or ottoman at the foot can help anchor the bed in the room. A large rug that extends beyond the sides of the bed softens the floor and frames the whole arrangement.

In both cases, coordinating the metal finish with other details, such as lamp bases or a mirror frame, makes the room feel considered.

Making the decision

If your room is comfortable rather than generous, you sleep alone or you are happy sharing a standard bed, a metal double is the practical choice. If you share the bed every night, one of you is tall or restless and your room has space to spare, a metal king will likely improve your sleep.

Measure carefully, mark the floor, and think about how you actually sleep rather than how the bed looks in a photograph. You can compare both sizes across our ranges at Furniture in Fashion, with free delivery to most UK mainland postcodes.

Common situations and what usually works

A couple in a compact flat

Where the main bedroom is modest, a slim metal double usually gives the best balance. It leaves space for a wardrobe and bedside tables and keeps the room feeling open. If you both sleep well on a double already, there is little reason to change.

A couple in a family house

Main bedrooms in many family homes can take a king comfortably. If children sometimes come into the bed in the early hours, the extra width makes those nights far more restful for everyone.

A single sleeper who wants space

A double offers generous room for one. A king is a pleasant extra if the room is large, but it is not essential.

A guest room

A double is usually the more practical choice, as guest rooms often serve other purposes too. It leaves space for a desk, a chair or storage.

Questions to ask yourselves

Do either of you wake when the other moves? Does anyone’s feet reach the end of your current mattress? Do children or pets regularly join you? Can you walk comfortably on both sides of a king outline in your room? Will you need room for a wardrobe or chest of drawers to open at the foot or sides of the bed?

If the answers to the first three questions are mostly yes and the room passes the floor test, a king will likely be worth it. If the room is tight or you already sleep well, a double keeps the space practical and comfortable. Either way, a slim metal frame helps you make the most of the floor you have.

It can also help to try both sizes in person if you have the chance, perhaps at the home of friends or family or in a hotel room. Lying on a king for a night or two often makes it clear whether the extra width feels necessary or simply pleasant.

Think, too, about the furniture you already own. Bedside tables that suit a double may look slightly small beside a king, and a rug sized for a double may not reach past the sides of a larger bed. These are small changes, but planning them at the same time helps the room feel finished rather than pieced together. A metal frame in a finish that matches existing lamps or handles makes the transition easier whichever size you choose.

Frequently asked questions

How much bigger is a king than a double?

A UK king is 15 cm wider and 10 cm longer than a double. The mattress measures 150 x 200 cm compared with 135 x 190 cm.

Is a double bed big enough for two adults?

Many couples sleep comfortably on a double. If either of you is tall or restless, a king can make a noticeable difference.

Will a king size bed fit in an average UK bedroom?

It depends on the room and the other furniture. Mark the outline on the floor and check that you can walk comfortably around it before deciding.

Do I need new bedding if I upgrade to a king?

Yes. Duvets, sheets and pillowcases need to match the larger mattress size.