MattressNextDay Medi Flex Waterproof Contract Single Mattress
The Medi Flex is a waterproof foam mattress built for practical settings: care environments, rental properties, children's rooms, anywhere spills and accidents are a real possibility.
- Breathable waterproof cover wipes clean
- Fire rated for care homes & rentals
- 10-year guarantee
£159
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MattressNextDay Medi Flex Waterproof Contract Mattress
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Mattress details
Mattress
MattressNextDay Medi Flex Waterproof Contract Mattress
Size
Firmness
Firm
Construction
Foam
Eco-Friendly
Depth (cm)
14
Layers
2
Layer Details
Waterproof Cover
A breathable waterproof cover, which means spills and accidents wipe away without soaking into the foam beneath. MattressNextDay describes it as just as comfortable as it is practical.
EcoFoam®
A material made from 100% recycled and re-engineered foam, giving a greener product with a reduced carbon footprint. This layer provides the mattress's firm support.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Suits bunk beds and mid sleepers: At 14cm deep, this UK single sits comfortably below the safety rail height most raised frames require, which taller mattresses often exceed.
- Right size for accident-prone years: The waterproof cover matters most in children's rooms, and the UK single is the standard children's bed size, so protection lands exactly where it's needed.
- Compact footprint for busy rooms: At 90cm wide, it leaves floor space for a desk, wardrobe and toy storage in a child's room, or a work setup in a spare room.
- Easy for multi-bed setups: Landlords, hostels and care settings furnishing several rooms will find a firm, wipe-clean UK single the practical unit to buy in multiples.
- Cheap, easy bedding: Single sheets and a standard 135 x 200cm single duvet fit, and both are the most widely stocked and affordable bedding sizes in the UK.
This size suits you if...
You're kitting out a child's or teenager's bed, a bunk or mid sleeper where a slim 14cm mattress is a safety requirement, or a rental, guest room or care setting where spills and accidents are a genuine possibility. It also suits a spare room that doubles as an office, where the bed needs to take up as little space as possible.
Consider another size if...
An adult couple will be sharing the bed, or an adult wants more sprawling room. We'd recommend the UK double instead, which is 45cm wider, gives 67.5cm each for two sharing, and needs a room of at least 2.6m x 2.8m.
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FAQ's
Will the Medi Flex UK single fit a bunk bed or mid sleeper?
Yes, and it's a natural match. At 90 x 190cm it fits standard UK bunk and cabin frames, and its 14cm depth is slim enough to keep a sleeper safely below the guard rail, which many deeper mattresses can't. Check your frame's stated maximum mattress depth before ordering, but 14cm passes almost all of them.
Is the Medi Flex single a good choice for a child's bedroom?
It's one of the strongest cases for this mattress. The UK single is the standard children's bed size, the waterproof cover copes with accidents without a crackly protector on top, and it's hypoallergenic. The firm feel suits growing sleepers, although an adult moving in permanently might find it a little spartan.
How much room does a UK single mattress need?
We suggest allowing at least 2.1m x 2.8m of floor space, which gives you room to walk alongside the bed and open drawers or a wardrobe. That makes the UK single the easiest size to place in box rooms, loft conversions with a narrow usable footprint, or a child's room competing with a desk and toy storage.
Can two Medi Flex singles work for siblings sharing a room?
Often better than one bigger bed. Two UK singles at 90cm wide each give both children their own space, and because this mattress is waterproof and firm, each bed copes with its own accidents independently. You'll need a room wide enough for both beds plus a walkway between them, so measure before committing.
Is a UK single big enough for an adult on the Medi Flex?
For occasional use, a guest room or a rental, yes: at 90cm wide it's the standard one-person size. For an adult's main bed we'd suggest sizing up to the UK small double of this mattress, which is 30cm wider, the same length, and needs a room of at least 2.4m x 2.8m.