Silentnight Comfort Breathe Plus 2100 Mattress
Mattress
Silentnight Comfort Breathe Plus 2100 Mattress
Size
Firmness
Construction
Depth (cm)
30
Layers
7
Layer Details
- Pillowtop sleep surface. A cushiony pillowtop in a naturally hypoallergenic fabric, which means immediate softness the moment you lie down. It's also a sensible choice if dust or allergens bother you at night.
- Comfort Breathe+. An Airloft comfort layer that Silentnight positions as a cooler, cocooning alternative to traditional foam, claiming 18x more breathability. In practice that means pressure-relieving softness with less heat build-up than a standard foam layer.
- 1500 nano springs. A layer of 1,500 ultra responsive nano springs that contour to your body. Because springs allow air to move where foam can't, this layer also helps the mattress breathe.
- Spring insulator layer. A polyester insulator layer with enhanced breathability, sitting between the comfort layers and the main spring unit. It keeps the layers above from settling into the springs below.
- 600 Mirapocket spring unit. 600 Mirapocket springs sit in individual pockets and respond independently to movement, which means zoned support and better spinal alignment. It also helps limit motion transfer if you share a bed.
- Protective Layer. This layer disperses pressure from the spring unit across the mattress. The aim is a longer usable life rather than any change to how it feels.
- Durable case. A soft, durable outer case designed to keep the mattress comfortable for years. It's the housekeeping layer rather than a comfort feature.
Layer details from silentnight.co.uk product page, September 2026.
- A shared size that fits real rooms: At 135 x 190cm, or 4ft 6in x 6ft 3in, it fits where a UK king would dominate; we suggest a room of at least 2.6m x 2.8m.
- 67.5cm each for two people sharing: That's each sleeper's own strip of the cushiony pillowtop, and the 600 Mirapocket springs move independently, so one of you turning shouldn't wake the other.
- Cooler for two bodies in one bed: Two people sharing generate more heat than one, and the Airloft layer plus 1,500 nano springs let air move where a foam pillowtop would trap it.
- Room for bedside tables on both sides: In a typical UK bedroom the double usually leaves space for a table each side, which a wider bed often doesn't.
- Easy to dress and easy to buy for: Double sheets and duvets are sold everywhere at every price point, a small saving that matters if you're furnishing a whole home at once.
This size suits you if...
You share the bed every night and want the traditional couples' size in a bedroom where a UK king would leave you squeezing past the footboard, or you sleep alone and want space to spread out, perhaps with a dog or cat claiming a corner of the pillowtop. It also suits a guest room that hosts visiting couples, since the medium feel works for most sleeping positions.
Consider another size if...
You're a couple with a larger room and either of you is a restless or sprawling sleeper. The UK king is 15cm wider and 10cm longer, and we'd recommend it if your room is at least 2.7m x 2.9m.
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Is the Comfort Breathe Plus 2100 UK double big enough for two adults?
For most couples, yes. You get 67.5cm each for two people sharing, and because the 600 Mirapocket springs respond independently, a partner shifting position is less disruptive than the width alone might suggest. If either of you is broad-shouldered or spreads out in the night, the UK king adds 15cm of width and 10cm of length.
What room size do I need for this mattress in a UK double?
We suggest a room of at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That allowance usually leaves space for a wardrobe and drawers alongside the bed, and bedside tables on both sides, which is why the UK double remains the default choice for typical British bedrooms.
Should I buy the Comfort Breathe Plus 2100 in a UK double or a UK king?
It comes down to your room. The UK king is 15cm wider and 10cm longer, and needs at least 2.7m x 2.9m by our guidance, against 2.6m x 2.8m for the UK double. If you're tall, the extra 10cm of length is the bigger win; if the room is snug, the UK double keeps walking space around the bed.
Will the UK double sleep cooler than a smaller size for a couple?
The cooling comes from the construction rather than the size: the Airloft layer and 1,500 nano springs let air circulate where foam would hold heat. What the UK double adds is separation. With 67.5cm each, you're less pressed against a warm partner than on the UK small double, which is 15cm narrower.
Is the UK double a good choice for a guest room?
It's the safest guest room size, since it comfortably takes a visiting couple or a solo guest, and the medium feel with a soft pillowtop surface suits most sleeping positions without you knowing your guests' preferences. Allow at least 2.6m x 2.8m so the room still takes a wardrobe and somewhere to put a suitcase.