Kaymed Heavy Sleeper 1200 Pocket Hybrid Mattress
Mattress
Kaymed Heavy Sleeper 1200 Pocket Hybrid Mattress
Size
Firmness
Firm
Construction
Depth (cm)
33
Layers
3
Layer Details
- Knitted cover. A soft knitted finish that adds a touch of cosiness and warmth on the surface. It's designed to help with airflow and breathability too, which matters on a firmer mattress where you sleep more on top than in it.
- Reflex Foam. A layer of high density reflex foam that supports spinal alignment, which means your back stays in a healthier position through the night. It's firm and durable rather than plush, so expect a solid feel from the first night.
- Pocket Springs. 1,200 individual springs, each encased in its own cloth pocket, adapt to your movement independently. That gives personalised support to different parts of your body and helps limit motion transfer from a partner.
Layer details from mattressonline.co.uk product page, September 2026.
- Firm support in a compact footprint: Most singles lean soft for children, so a genuinely firm single is a rarer find for heavier teens and adults sleeping alone.
- A narrow bed that stays stable: High density reflex foam over pocket springs gives a solid, even surface, which means less roll-toward-the-edge feeling than a softer single.
- Fits compact rooms: At 3ft x 6ft 3in it leaves floor space for a desk or wardrobe, and we suggest a room of at least 2.1m x 2.8m.
- Sensible for a spare room: The firm, supportive feel suits occasional guests of different weights better than a soft mattress tuned to one person.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm single duvet fit, and both are the most widely stocked bedding of any UK size.
This size suits you if...
You're a heavier teen or adult sleeping alone and most singles feel too soft under you, or you're kitting out a spare room and want a firm surface that suits a range of guests. It also fits a student room or first flat where the frame is provided and you only need the mattress, provided you like a solid, sleep-on-top feel rather than a cushioned one.
Consider another size if...
You're an adult who wants real stretching room, or two of you will share the bed. The UK double is 45cm wider at the same length, and we suggest a room of at least 2.6m x 2.8m for it.
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Will the Kaymed Heavy Sleeper 1200 UK single fit a bunk or mid sleeper frame?
Be careful here. This mattress is 33cm deep, which is unusually tall for a raised frame, so on a bunk it could sit above the safety rail and on a mid sleeper it may reduce headroom badly. Check your frame's maximum mattress depth before buying; many bunks specify a much shallower limit.
What room size do I need for the Kaymed Heavy Sleeper 1200 in a UK single?
The mattress itself is 90 x 190cm, and we suggest allowing at least 2.1m x 2.8m of floor space so you can walk around the bed and open drawers or wardrobe doors comfortably. That's our own guidance, not Kaymed's. In a child's room it leaves usable space for a desk and toy storage alongside the bed.
Is the Kaymed Heavy Sleeper 1200 single a good choice for a child?
It depends on the child. This is a firm mattress, and lightweight children may find it too unyielding, particularly if they sleep on their side. For a heavier teenager who has outgrown a softer children's mattress, the firm pocket-sprung support makes more sense. The 33cm depth also rules out many bunk and cabin frames.
Is a UK single big enough for an adult on this mattress?
For one adult sleeping alone, yes: 90cm of width is the standard UK one-person size, and the firm surface means you sleep on top rather than sinking toward the middle. If you're broad-shouldered or move around a lot at night, the UK double is 45cm wider at the same length and worth considering.
Where can I compare prices for the Kaymed Heavy Sleeper 1200 UK single?
Use the price table on this page. The prices shown here are updated as retailers change them, so it's the quickest way to see current UK single pricing rather than checking sites one by one. Availability for this size can shift, so compare the retailers listed on this page before you commit.