Silentnight Plant Based Box Top 1800 Mattress
Mattress
Silentnight Plant Based Box Top 1800 Mattress
Size
Firmness
Medium
Construction
Depth (cm)
31
Layers
4
Layer Details
- Tencel™ Lyocell sleep surface. A silky, soft touch top layer woven to allow airflow and carry moisture away from you as you sleep. In practice, that means a cooler, drier feel through the night.
- Platinum comfort layer. Silentnight says this layer is ten times more breathable than memory foam while offering the same pressure relief. You get that cocooning, contouring feel with less of the heat build-up memory foam is known for.
- Plant Based Comfort Layer. A cushioning layer made from a combination of bamboo, kapok, flax and aloe vera, which Silentnight says is sustainably sourced. This is where the mattress gets its plant based name and much of its soft, breathable character.
- Mirapocket® springs and mini springs. 800 Mirapocket springs adjust to your movements through the night, combined with 1000 mini springs for extra comfort and breathability. Each spring works independently, which means better isolation of movement between you and a partner.
Layer details from silentnight.co.uk product page, September 2026.
- Slots into small rooms: At 90cm wide it leaves room for a desk, wardrobe and toy storage in a compact bedroom, which matters when the bed is competing for floor space.
- A step up for a spare room: The bamboo, kapok, flax and aloe vera comfort layers give guests a softer, more cushioned welcome than the thin mattresses spare beds usually get.
- Quiet support for restless kids and teens: The 800 Mirapocket springs move independently, so a fidgety sleeper settles into consistent support rather than rolling toward a dip.
- Cooler for warm sleepers: The Tencel Lyocell surface is woven to let air through and carry moisture away, useful in a small room or a loft that holds heat.
- Check raised frames first: Yes, the 31cm depth gives that full box top feel, but on a bunk, cabin or mid sleeper it can leave too little guardrail showing, so measure before you buy.
This size suits you if...
You're buying for one sleeper, a child moving up from a cot bed, a teenager, or an adult with a compact room, and you want natural materials with proper spring support rather than a basic budget mattress. It also suits a spare room or a study that doubles as guest space, where a 90cm footprint keeps the room usable the rest of the week.
Consider another size if...
You share the bed, or you want space to properly stretch out. We'd recommend the UK super king instead: it's 90cm wider and 10cm longer than the UK single, and we suggest allowing at least 3m x 2.9m for it.
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Will the Silentnight Plant Based Box Top 1800 UK single fit a bunk bed?
The 90 x 190cm footprint matches standard bunk and mid sleeper frames, but the depth is the real question. At 31cm, this mattress may sit too high against a top bunk's guardrail to be safe for a child. Measure from the frame base to the top of the guardrail before buying, particularly for the upper bunk.
What room size do I need for a UK single Silentnight Plant Based Box Top?
We suggest allowing at least 2.1m x 2.8m of floor space. That gives you room to walk alongside the bed and open a wardrobe, which is why the UK single works in box rooms, lofts with a narrow flat section, and children's bedrooms where a desk and storage are fighting for the same wall.
Is the UK single Plant Based Box Top a good choice for a child or teenager?
For most, yes. The medium tension with a cushioned box top suits growing sleepers who don't need a firm, flat surface, and the breathable Tencel Lyocell top helps in warm bedrooms. Lightweight children may sit more on the plush top layers than in them, which is comfortable but a softer feel than a traditional sprung mattress.
Do standard single fitted sheets fit this mattress?
Shallow ones may struggle. The mattress is 90 x 190cm, so single sheets are the right size on paper, but the 31cm depth means many standard fitted sheets won't tuck fully under. Look for deep or extra deep single fitted sheets and check the stated depth on the packaging before you buy.
How much bigger is the UK super king than the UK single?
The UK single is 90cm narrower and 10cm shorter than the UK super king, which is a substantial jump. If two of you will sleep on this mattress every night, the UK super king is the sibling size to consider, and we suggest a room of at least 3m x 2.9m for it.