Hypnos Wool Tranquility Small Double Mattress
The Hypnos Wool Tranquility is a medium firm pocket sprung mattress built around natural fibres: sustainably sourced British wool and cotton over 1400 of Hypnos's ReActive 8-turn pocket springs.
- Less clammy than all-foam beds
- Hips sink in, shoulders stay supported
- Suits back & combination sleepers
£849
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Hypnos Wool Tranquility Mattress
More available sizes
Mattress details
Mattress
Hypnos Wool Tranquility Mattress
Size
Firmness
Medium Firm
Construction
Wool
Depth (cm)
29
Layers
5
Layer Details
Viscose Blend Breathable Sleep Surface
A soft viscose blend cover that promotes airflow, which means the sleep surface stays cooler and fresher through the night.
Sustainably Sourced British Wool
British wool gives gentle cushioning with impressive resilience. In practice that means a comfort layer that keeps its shape rather than developing body impressions quickly.
Sustainably Sourced Cotton
Natural cotton fibres are highly breathable and wick away excess moisture. You'll feel this as a cooler, drier surface, particularly useful if you tend to overheat.
eOlus™ Fibres
These fibres offer a soft, foam-like feel while letting air and moisture pass through easily. You get the comfort of foam without the heat retention it's often criticised for.
ReActive™ 8-Turn Pocket Springs
The base is 1400 individually responsive pocket springs, each with 8 turns, engineered for total spinal and body support. Each spring senses and adjusts independently, so movement on one side of the bed is less likely to disturb the other.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Real stretching room for one: The UK small double is 30cm wider than the UK single, which means a solo sleeper can shift position freely without a hip or elbow hanging over the edge.
- Fits rooms a double crowds: It's 15cm narrower than the UK double, and in a box room or loft conversion that can be the difference between walking round the bed and squeezing past it.
- Breathable fibres in a smaller footprint: Wool and cotton wick moisture away, so a solo sleeper who runs warm gets a cooler surface without needing a bigger bed to spread heat across.
- Springs that suit occasional sharing: The 1400 pocket springs respond independently, so when a guest room couple shares the 120cm width, one person turning is less likely to wake the other.
- Standard 4ft bedding and frames: The small double is an established UK size, so fitted sheets and bed frames are easy to find, which matters if you're kitting out a guest or rental room.
This size suits you if...
You're a solo adult who has outgrown a single but your room can't take a full double, you're furnishing a guest room where couples stay for a night or two rather than every night, or you're downsizing and the bed has to fit the new room's dimensions rather than the old one's.
Consider another size if...
You share the bed every night, because 120cm gets tight for two adults long term. We'd recommend the UK double instead, which is 15cm wider and the same length; allow a room of at least 2.6m x 2.8m for it.
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FAQ's
Is the Hypnos Wool Tranquility small double big enough for a couple?
For occasional nights, yes. Across a 120cm width the individually responsive pocket springs help limit disturbance when one person moves, and the breathable wool surface stays drier with two bodies on it. For a couple sharing every night, though, the UK double or UK king of this mattress would be the more comfortable choice.
What room size do I need for a small double mattress?
We suggest a room of at least 2.4m x 2.8m for the UK small double. That allows walking space along the sides and clearance for the door and a wardrobe. It's our guidance rather than the manufacturer's, so treat it as a sensible minimum, not a strict rule, and measure your own layout first.
How much wider is a small double than a single?
The UK small double is 30cm wider than the UK single, and both are the same 190cm length. That extra width is the whole point of the size: a teenager or adult who's outgrown a single gains genuine spreading room while the bed's footprint grows far less than a move to a double would demand.
Would the Hypnos Wool Tranquility in a small double suit a loft conversion?
Often, yes. Sloping ceilings usually leave a narrow strip of full standing height, and at 15cm narrower than the UK double the small double can sit within it where a bigger bed couldn't. One practical note: this mattress is delivered flat rather than rolled, so check your staircase and any turns before ordering.
Where can I buy the Hypnos Wool Tranquility in a UK small double?
Compare the retailers listed on this page; the prices shown are updated as retailers change them, so what you see reflects current stock rather than a snapshot. Stockists for individual sizes do shift over time, which is why we'd always check the live table rather than rely on an older review or listing.