Silentnight 3 Zone Memory Foam Mattress
Mattress
Silentnight 3 Zone Memory Foam Mattress
Size
Firmness
Construction
Depth (cm)
18
Layers
2
Layer Details
- Soft Knitted Sleep Surface. A soft, breathable knitted cover that adds a touch of comfort at the surface. It takes a little of the edge off the firm feel beneath.
- Memory Foam. Body-moulding memory foam that responds to your shape, which means pressure points at the hips and shoulders get some relief. Expect a contouring, cradled feel rather than bounce.
Layer details from mattressnextday.co.uk product page, September 2026.
- Real room to spread out alone: At 4ft x 6ft 3in you can stretch, turn and change position freely, which a UK single rarely allows an adult to do comfortably.
- Fits rooms a double crowds: It's 15cm narrower than a UK double, often the difference between a door that clears the bed and one that doesn't.
- Firm feel across the extra width: The solid, supportive foam base means you won't roll toward the middle when you shift across the wider surface.
- Low profile for tight spaces: The 18cm depth keeps the bed visually low, slimmer than many mattresses, but helpful in loft rooms with sloping ceilings.
- Standard 4ft bedding and frames: The UK small double is a standard British size, so small double fitted sheets and frames are easy to find on the high street.
This size suits you if...
You sleep alone and have outgrown a UK single but your room can't take a full double, you're furnishing a guest room or holiday let where couples stay occasionally rather than nightly, or you're kitting out a teenager's bedroom and want them to keep some floor space. Allow at least 2.4m x 2.8m of room and the UK small double works well here.
Consider another size if...
You share the bed every night, since 120cm of width feels tight for two adults over the long term. We'd recommend the UK double instead, allowing at least 2.6m x 2.8m of room for it.
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Is a small double memory foam mattress big enough for one adult?
Comfortably, yes. The UK small double is 30cm wider than a UK single at the same length, so an adult who likes to spread out or change position has genuine room to do it. The firm foam here holds its shape across that width, so you stay supported wherever on the surface you settle.
Can a couple share the Silentnight 3 Zone in a UK small double?
For occasional nights, yes, which is why it suits guest rooms and holiday lets. For every night, 120cm split between two adults is snug, and the firm feel means neither of you sinks into a shared dip. If you'll share regularly, the UK double is the better buy; allow at least 2.4m x 2.8m for the small double itself.
Will the small double fit in a box room or studio flat?
Usually, and that's its main appeal. We suggest a room of at least 2.4m x 2.8m, which leaves space to open the door and walk one side of the bed. Being 15cm narrower than a UK double is often what keeps a wardrobe usable in a compact bedroom.
What bed frame do I need for this size?
A standard UK small double frame, sometimes labelled 4ft. The mattress measures 120 x 190cm, so check the frame's internal dimensions match. Its 18cm depth sits lower on the frame than taller mattresses, which some people like in rooms with sloping ceilings and others find a little shallow next to a divan.
Is the UK small double a good size for a teenager?
It's a sensible step up. A teenager who has outgrown a UK single gains 30cm of width without losing the length, and the room keeps more floor space than a UK double would allow. The firm feel of this Silentnight suits growing sleepers who tend to find soft foams too sink-in.