Silentnight Comfort Breathe Plus 2100 Small Double Mattress
The Silentnight Comfort Breathe Plus 2100 is a medium-feel pillowtop mattress built around 2,100 springs in total: 1,500 nano springs for contouring and 600 Mirapocket springs for zoned support underneath.
- Soft pillowtop that stays cool
- Nano springs contour to your body
- 60-night trial & 5-year guarantee
£799
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Silentnight Comfort Breathe Plus 2100 Mattress
More available sizes
Mattress details
Mattress
Silentnight Comfort Breathe Plus 2100 Mattress
Size
Firmness
Medium
Construction
Foam
Pocket Spring
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.
Key benefits
- Real space to sprawl alone: The UK small double is 30cm wider than the UK single, which means a solo adult can stretch out on the pillowtop rather than sleeping to attention.
- Fits where a double will not: At 15cm narrower than the UK double, this size can be the difference between a bed fitting a box room or blocking the door.
- Breathability in a small room: Compact bedrooms can run warm, so the Airloft layer and 1,500 nano springs adding airflow matter slightly more here than in a larger, airier room.
- Sensible for occasional guests: The 600 Mirapocket springs limit motion transfer, so a visiting couple can share for a night or two without every turn being felt.
- Easy to dress and frame: 4ft is a standard UK size, so small double fitted sheets and frames are easy to find, and a standard double duvet drapes generously.
This size suits you if...
You sleep alone most nights and have outgrown a UK single but your room can't take a full double, or you're furnishing a guest room or small second bedroom where couples stay occasionally rather than nightly. It also makes sense for a teenager who needs more width without losing floor space. Allow at least 2.4m x 2.8m of room so you can still move around the bed.
Consider another size if...
You share the bed every night, because 120cm between two adults gets tight quickly on a soft pillowtop. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m for it.
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FAQ's
Is the small double Comfort Breathe Plus 2100 big enough for two adults?
For the occasional night, yes. The pocket springs keep movement from travelling across the bed, so sharing is comfortable enough for guests. Every night is a different matter: 120cm across two people leaves less personal width than a UK single each, and the soft pillowtop means you'll feel a partner rolling towards the middle more than on a firmer surface.
What size room do I need for a small double mattress?
We suggest at least 2.4m x 2.8m for a UK small double. That leaves enough clearance to walk round the bed, open drawers and change the sheets without shuffling sideways. In a box room or loft conversion, measure where the door swings and where the ceiling slopes before you decide, since those often matter more than the floor area itself.
What are the dimensions of the Comfort Breathe Plus 2100 in a UK small double?
It measures 120 x 190cm, which is 4ft x 6ft 3in. That's the same length as a UK single and a UK double, so it fits along the same wall as either; only the width changes. Small double (4ft) fitted sheets are the right bedding, and a standard double duvet works well on top.
Is the UK small double a good upgrade from a single for a teenager?
Often, yes. The UK small double is 30cm wider than the UK single and exactly the same length, so a teenager gets noticeably more room to turn over without the bed eating more of the floor lengthways. The medium feel with a cushiony top suits lighter sleepers well, though a heavier front sleeper may find it a little soft.
Does the Comfort Breathe Plus 2100 feel softer in a small double?
No, the construction is identical across sizes: the same pillowtop, Airloft layer, 1,500 nano springs and 600 Mirapocket unit. What changes is how you use it. Sleeping solo in this size, you can drift across the full width, whereas a couple sharing 120cm will each settle into one spot, which concentrates wear. Rotate it regularly either way.