Silentnight Miracoil Memory Cushion Top Mattress
Mattress
Silentnight Miracoil Memory Cushion Top Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
24
Layers
3
Layer Details
- Cushion Top. A deep-filled cushion top stuffed with extra soft fillings, which means a gentler first impression when you lie down. It softens the surface without changing the firm support beneath.
- Eco Comfort Layer. Silentnight's Eco Comfort layer uses fibres partially made from recycled plastic, including bottles. It's breathable and helps regulate temperature and reduce moisture build-up, so you should feel a little less clammy on warm nights.
- Miracoil Spring System. Silentnight's exclusive Miracoil spring system provides zoned support, which means firmer reinforcement where your body carries more weight. It also supports you right to the edge of the mattress, so you can use the full sleep surface without feeling you'll fall off.
Layer details from silentnight.co.uk product page, September 2026.
- Real space for one sleeper: The UK small double is 30cm wider than the UK single, which means a solo adult can stretch, roll and change position freely.
- Fits rooms a double cannot: At 15cm narrower than a UK double, it leaves usable floor space in box rooms, lofts and compact second bedrooms.
- Edge support matters more at 4ft: The Miracoil springs support you right to the edge, so on a narrower mattress you can genuinely use all 120cm of the width.
- Firm feel suits solo spread-out sleeping: Zoned springs firm up under your hips and shoulders wherever you settle, which means consistent support even if you drift across the mattress.
- Standard UK sizing: 4ft is a stock British size, so small double frames, fitted sheets and bases are easy to find on the high street.
- Occasional couple use works: Two guests can share it comfortably for a weekend, helped by that edge-to-edge support, making it a sensible guest room pick.
This size suits you if...
You sleep alone and have outgrown a single but your room can't spare the width of a full double, you're furnishing a guest room or loft conversion where couples visit occasionally rather than nightly, or you're downsizing and need the bed to fit the new room rather than the old one. The firm, springy feel rewards back and front sleepers who like solid support.
Consider another size if...
You share the bed every night, as 120cm is tight for two over the long term. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m of room for it.
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What are the dimensions of the Silentnight Miracoil Memory Cushion Top small double?
This size measures 120 x 190cm, which is 4ft x 6ft 3in. Silentnight's Miracoil springs support the full surface right to the edge, so you get usable width across all 120cm rather than a soft border you avoid. We suggest a bedroom of at least 2.4m x 2.8m to fit it comfortably.
Can a couple sleep on the Silentnight Miracoil in a UK small double?
For occasional nights, yes. The edge-to-edge spring support helps two people use the whole width, and the firm base limits roll-together. For every night, 120cm is a squeeze for most couples, and the firmer feel makes bumping elbows more noticeable. Nightly sharers would be happier in the UK double, which is 15cm wider.
Will the UK small double fit in a box room or loft conversion?
Usually, and that's its main appeal. We suggest a minimum room of 2.4m x 2.8m, which leaves space to walk around and open the door. In a loft with sloping ceilings, the 15cm saved against a UK double can be the difference between a bed that works and one that blocks the room.
Should I choose this mattress in a small double or a double?
Pick the UK small double if you sleep alone and the room is tight: it's 15cm narrower than the UK double and the same length. If you share nightly, or your room meets our suggested 2.6m x 2.8m for the UK double, size up. The feel and construction are identical, so it's purely a space decision.
Is this a good guest room mattress in a small double?
It's a strong fit. The size handles a solo guest generously and a visiting couple for short stays, and the firm zoned support tends to suit a wide range of unknown sleepers better than a very soft mattress would. The breathable Eco Comfort layer also helps a bed that sits unused stay fresher between visits.