Hypnos Alcester Ortho Extra Mattress
Mattress
Hypnos Alcester Ortho Extra Mattress
Size
Firmness
Firm
Construction
Depth (cm)
27
Layers
4
Layer Details
- Damask cover. A finely woven, durable fabric that feels soft to the touch. It doesn't retain heat, which means it stays cooler against you through the night.
- Cotton. Breathable cotton fibres that wick away moisture. In practice that keeps you dry and cool rather than clammy.
- Solotex™. A filling engineered from recycled plastic, so it's an eco-friendlier choice. It's extremely durable and cuddles body contours for a slightly softer feel over the firm springs.
- Pocket Springs. 1,200 ReActivePro 6-turn pocket springs with tighter spring resistance. That means a more supportive surface that still adapts to your unique shape, weight and movement.
Layer details from mattressonline.co.uk product page, September 2026.
- Fits a compact room: At 90cm wide it leaves floor space free in a child's room that already has to hold a wardrobe, a desk and toy storage.
- Firm support for growing sleepers: The 1,200 ReActivePro pocket springs give teenagers and single adults a properly supportive surface, which means less sag as they get heavier over the years.
- Flippable for a long life: It can be rotated and flipped for even wear, useful in a single that may serve a child right through their teens.
- Sensible for spare rooms: In a spare room that doubles as an office, the 3ft width keeps the desk usable while still giving guests a full-length bed.
- Cool for smaller spaces: The breathable cotton and non-heat-retaining damask cover matter more in a box room, where warm air has less space to circulate.
This size suits you if...
You're buying for a child or teenager and want a firm, flippable mattress that lasts through the growing years, you sleep alone and your bedroom or loft conversion only takes a narrow footprint, or you're kitting out a spare room that needs to earn double duty as an office or occasional guest space.
Consider another size if...
You're an adult who sleeps alone but wants room to stretch, or you share 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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Is a UK single Hypnos Alcester Ortho Extra big enough for an adult?
Yes, for one person. At 90 x 190cm (3ft x 6ft 3in) it's the standard UK one-person size, so a single adult gets full-length support. It suits back and front sleepers best given the firm feel. If you tend to spread out or share occasionally, the UK small double gives you 30cm more width at the same length.
What room size do I need for the Hypnos Alcester in a UK single?
We suggest allowing at least 2.1m x 2.8m of floor space. That leaves enough room to walk around the bed and open drawers or wardrobe doors without squeezing past. In a loft conversion, position the 90cm-wide footprint along the tallest wall and the sloped ceiling becomes much less of a problem.
Will the UK single Hypnos Alcester Ortho Extra work on a bunk or mid sleeper?
The 90 x 190cm footprint matches standard UK bunk and mid-sleeper frames, but check depth before buying. This mattress is 27cm deep, which is more than many raised frames allow, and a mattress that sits above the guard rail is a safety issue. Measure from the base to the top of the rail first.
Is this mattress too firm for a child in a single bed?
Possibly, depending on how they sleep. It's a firm mattress, and lightweight side sleepers may find it presses on shoulders and hips rather than letting them settle in. A child who sleeps on their back or front should get on well with it, and the firm springs will hold up as they grow.
Should I buy the UK single or the UK small double for a spare room?
It depends on who visits. The UK single suits a spare room that also works as an office, or a guest room fitting two separate beds. If couples stay regularly, the UK small double is 30cm wider at the same length; allow at least 2.4m x 2.8m for it. Compare the retailers listed on this page for either size.