Hypnos Cawthorne Support Mattress
Mattress
Hypnos Cawthorne Support Mattress
Size
Firmness
Firm
Construction
Depth (cm)
25
Layers
7
Layer Details
- Cover. A soft to touch Belgian damask cover, which gives a more traditional, upholstered feel than a knitted stretch fabric.
- Comfort layer. A blend of cotton and polyester that combines their comforting properties with increased breathability and moisture wicking. In practice, that means less clamminess on warmer nights.
- eOlus fibres. Hypnos' exclusive eOlus fibres are made from recycled materials and spun into breathable fibres that promote airflow to dispel heat. They also contribute to the secure, firmer feel this mattress is built around.
- Soft White Fibres. Soft synthetic fillings that create a cosy feel while staying durable and resilient. They're designed to maintain their shape rather than compressing into dips over time.
- Support pad. A dual density polyester pad that protects the spring unit and encourages equal weight distribution, which means the springs beneath wear evenly.
- Spring core. 1200 ReActive springs, each sitting in its own fabric pocket to increase responsiveness and isolate movement. You should feel less of a partner shifting about on the other side.
- Edge support. The outer rows of springs use a firmer gauge, reinforced with a durable rod edge. That gives you a sturdier perimeter for sitting on the edge and makes the full sleeping surface usable.
Layer details from mattressonline.co.uk product page, September 2026.
- Fits the smallest rooms: At 90 x 190cm, this size leaves floor space free in a child's room that also has to hold a wardrobe, desk and toy storage.
- Firm support for growing sleepers: The genuinely firm feel suits children and teens, whose backs benefit from solid, even support rather than a soft, sink-in surface.
- Usable right to the edge: Firmer gauge outer springs and a rod edge make the full 3ft width sleepable, which matters more here than on any wider size.
- Works on raised frames: At 25cm deep, it's a sensible candidate for cabin and mid sleeper frames, though check the frame's maximum mattress depth and guard rail height first.
- Guest room friendly: Two UK singles suit a spare room better than one double when guests are often friends or relatives who'd rather not share a bed.
- Cheap, easy bedding: Single sheets and duvets are the most widely stocked of any size, handy for guest beds and student rooms that need spares.
This size suits you if...
You're buying for a child or teenager who needs firm, supportive springs rather than foam, you're a single adult sleeper happy with a solid feel in a compact room, or you're kitting out a guest room or spare-room office where a 3ft footprint is all the space allows.
Consider another size if...
You're an adult who spreads out at night or shares the bed even occasionally. We'd recommend the UK small double instead: it's 30cm wider than the UK single, the same length, and we suggest at least 2.4m x 2.8m of floor space for it.
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What size is the Hypnos Cawthorne Support in a UK single?
It measures 90 x 190cm, which is 3ft x 6ft 3in, the standard UK one-person size. We suggest allowing at least 2.1m x 2.8m of floor space, which leaves room to walk round the bed and open drawers. That guidance is ours rather than the manufacturer's, so treat it as a sensible minimum, not a rule.
Will the Hypnos Cawthorne single work on a bunk or mid sleeper frame?
Often, yes. The UK single is the standard size for bunk and cabin frames, and at 25cm deep the Cawthorne is slimmer than many hybrids. Do check your frame's stated maximum mattress depth and make sure the guard rail still sits well above the sleeping surface before you buy.
Is the Hypnos Cawthorne UK single a good guest bed?
It's a strong candidate. The firm pocket spring feel suits occasional use because the fillings are designed to hold their shape rather than dip, and the reinforced edge means guests can sit on the side to dress without sliding off. Two singles also give a spare room more flexibility than one double.
Is a UK single big enough for an adult on this mattress?
For one adult who sleeps fairly still, yes, and the firmer edge springs help because the full 90cm width is usable. If you tend to sprawl, or you're taller than average, the UK single may feel restrictive. The Cawthorne's firm feel also means you won't sink into the middle, which makes a narrow mattress easier to live with.
Should I choose the UK single or the UK small double Hypnos Cawthorne?
The UK single is 30cm narrower than the UK small double, and the two are the same length. For a child, teen or a tight room, the UK single is the practical pick. A solo adult who wants space to stretch out would be better served by the UK small double, provided the room offers at least 2.4m x 2.8m.