Silentnight Comfort Breathe 800 Mattress
Mattress
Silentnight Comfort Breathe 800 Mattress
Size
Firmness
Construction
Depth (cm)
25
Layers
5
Layer Details
- Sleep surface. A naturally hypoallergenic fabric that's soft and gentle on the skin. A reassuring choice if you're sensitive to allergens.
- Comfort Breathe®. Silentnight describes these fibres as 15x more breathable than standard memory foam, promoting airflow and regulating temperature. In practice, that means a cooler surface for hot sleepers.
- 800 Mirapocket spring unit. 800 individual pocket springs respond separately to your body's movements, which means zoned support and better spinal alignment. You shouldn't roll towards a partner every time they turn over.
- Protective Layer. This layer disperses pressure from the spring unit across the mattress. It's there to help the mattress last longer.
- Durable case. A soft, hard-wearing case designed to keep the mattress comfortable for years to come.
Layer details from silentnight.co.uk product page, September 2026.
- Room to sleep apart, together: With 75cm each for two people sharing, you can settle into your own space rather than negotiating the middle of the bed all night.
- Pocket springs work better with width: The 800 individual springs respond to each sleeper separately, and the UK king's extra width means your partner's movements happen further away from you.
- Length for taller sleepers: At 200cm long, the UK king is 10cm longer than the UK Double, which matters more than width if one of you is nearing six foot.
- Cooler across a bigger surface: The Comfort Breathe fibre layer promotes airflow across the full 150cm width, so two warm bodies aren't sharing one small pocket of heat.
- An affordable route to the upgrade size: This sits at the budget end of the market, so moving up to a UK king costs less here than with most premium models.
This size suits you if...
You share the bed every night and the double has started to feel like a compromise, especially if one of you gets up hours before the other and you'd rather not feel every movement. It also suits you if one partner is tall, since the 200cm length removes the feet-off-the-end problem, or if a dog has quietly claimed a corner and you both need the space back.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case we'd recommend the UK double instead, allowing at least 2.6m x 2.8m for it.
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Is the Silentnight Comfort Breathe 800 king big enough for a couple?
Yes, comfortably for most. You get 75cm each for two people sharing, and because the 800 pocket springs move independently, that width does real work: your partner shifting position stays on their side of the mattress. A restless sleeper or a pet joining you overnight is where the extra space over a double proves itself.
Will a king size Comfort Breathe 800 fit in my bedroom?
We suggest a room of at least 2.7m x 2.9m for a UK king, which leaves space to walk round the bed and open drawers. New build master bedrooms can be tighter than they look once wardrobes go in, so measure the usable floor rather than the room. If it's a squeeze, the UK double needs at least 2.6m x 2.8m.
Is the UK king long enough for a tall sleeper?
At 200cm, it should be. The UK king is 10cm longer than the UK Double, and for anyone approaching six foot that extra length is often the real reason to size up. If you want more length still, the UK Super King is the same length as the UK king, so going bigger buys width, not extra legroom.
Does the Comfort Breathe 800 reduce partner disturbance in a king?
The 800 Mirapocket springs respond individually rather than moving as one block, so movement on one side transfers less to the other. In a UK king the effect is stronger simply because you're further apart. If one of you leaves for work hours before the other, that combination of independent springs and space is what lets the later riser sleep on.
Should we get the Comfort Breathe 800 in a king or super king?
The UK king suits most couples: a clear step up from a double without demanding a huge room. The UK Super King is 30cm wider than the UK king, worth it if a child or dog regularly joins you, but we suggest at least 3m x 2.9m of room for it. Compare the retailers listed on this page for both sizes.