MattressNextDay Kids Waterproof Foam Mattress
Mattress
MattressNextDay Kids Waterproof Foam Mattress
Size
Firmness
Construction
Depth (cm)
14
Layers
2
Layer Details
- EcoFoam®. A firm, orthopaedic foam layer made from 100% recycled and re-engineered foam, which means solid, even support for a growing child. It's highly breathable, pressure-relieving and naturally dust mite resistant, and the resilient construction should hold its shape well over time.
- Waterproof Cover. A breathable waterproof cover that protects the foam from accidents without making the surface feel sweaty. It's removable and machine-washable, and you can simply wipe it clean for little spills.
Layer details from mattressnextday.co.uk product page, September 2026.
- Made for raised frames: The 14cm depth is slim enough for bunk beds, cabin beds and mid sleepers, where a deeper mattress can sit above the safety rail.
- Fits the smallest bedrooms: At 3ft wide, a UK single leaves floor space for a wardrobe, desk and toy storage, and we suggest allowing at least 2.1m x 2.8m.
- Works for siblings sharing: The narrow 90cm footprint means two singles plus a walkway can fit in one room, something no larger size manages as comfortably.
- Accidents stay manageable: The waterproof cover unzips for the washing machine and wipes clean for spills, so the foam core underneath stays protected through the bedwetting years.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm single duvet fit, and both are the most widely stocked and affordable bedding of any UK size.
This size suits you if...
You're buying for a child's bed, bunk or mid sleeper and want a mattress that shrugs off accidents, or you're kitting out a shared kids' room where two 90cm-wide beds need to fit with space to walk between them. The firm, dust mite resistant foam also makes sense if your child has allergies and you want a surface that's simple to keep clean.
Consider another size if...
You need a mattress for an adult or a growing teenager. At 14cm this is slimmer and firmer than a standard adult foam mattress, and it only comes in a UK single, so look at a full-depth adult mattress instead.
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Will the MattressNextDay kids mattress fit a bunk bed or mid sleeper?
Yes, and it's one of the better matches for raised frames. It's a standard UK single at 90 x 190cm, the size most bunks and mid sleepers are built around, and the 14cm depth keeps the sleeping surface low relative to the safety rail. Check your frame's maximum mattress depth before ordering, but 14cm is comfortably slim by children's mattress standards.
What are the dimensions of the MattressNextDay kids waterproof mattress?
It measures 90 x 190cm, which is 3ft x 6ft 3in, the standard UK single. That's the default size for children's bed frames, bunks and cabin beds sold in the UK, so it should drop straight into most kids' frames without any measuring headaches. The mattress is 14cm deep.
How much floor space does a UK single need in a child's room?
We suggest allowing at least 2.1m x 2.8m. That gives room to get in and out of bed and open drawers, though in a child's room the bed is usually competing with a wardrobe, a desk and toy storage, so measure with those in place. The single's 90cm width is what keeps all of that workable.
Can you fit two of these UK singles in a shared children's room?
Often, yes. Two beds at 90cm wide plus a walkway between them will fit in many UK children's rooms where a larger bed would dominate. Because this mattress only comes as a UK single, buying a matching pair is straightforward, and each child gets their own waterproof, machine-washable cover, which makes accidents easier to deal with separately.
Is the UK single version of this mattress okay for an adult?
We wouldn't recommend it. Although a UK single is a standard adult size at 90 x 190cm, this particular mattress is designed for children: at 14cm it's slimmer than a typical adult foam mattress, and the firm EcoFoam® is tuned for lighter, growing bodies. It's fine for the occasional overnight guest, but adults should choose a full-depth mattress.