MattressNextDay Medi Flex Waterproof Contract Small Double 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
£199
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MattressNextDay Medi Flex Waterproof Contract Mattress
More available sizes
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
- Real width for one sleeper: At 120cm across, the UK small double is 30cm wider than the UK single, so a solo adult can sprawl without paying for space they never use.
- Fits rooms a double cannot: It's 15cm narrower than the UK double at the same length, which can be the difference between a door that clears and one that doesn't.
- Practical for lets and guest rooms: The waterproof cover handles spills and accidents in a holiday let or rental second bedroom, where you can't control how the bed gets used.
- Copes with the occasional couple: Two guests can share for a night or a weekend, though the firm 14cm foam build is better suited to occasional sharing than nightly couple use.
- A greener firm foam core: EcoFoam® is made from 100% recycled and re-engineered foam, which means firm support with a smaller carbon footprint than standard foam at this level.
This size suits you if...
You're kitting out a rental, holiday let or guest room with a small second bedroom, where 4ft gives visiting couples enough width without swallowing the floor; you sleep alone and want more room than a UK single offers without stepping up to a full double; or you need waterproof, compliant bedding in a compact care or hostel room where a wider mattress simply won't fit.
Consider another size if...
Two of you will sleep on it every night, or your room comfortably takes a bigger bed. We'd recommend the UK double instead: it's 15cm wider, giving 67.5cm each for two sharing, and we suggest at least 2.6m x 2.8m for it.
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FAQ's
Is the Medi Flex small double big enough for two adults?
For occasional nights, yes. At 120cm wide, two guests can share comfortably enough for a weekend stay, which is why the UK small double suits guest rooms and holiday lets. For a couple sleeping on it every night, the UK double gives 67.5cm of width each and is the better long-term choice, especially given this mattress's firm feel.
What room size do I need for a small double Medi Flex?
We suggest allowing at least 2.4m x 2.8m of floor space for the UK small double. That leaves room to walk around the bed and open the door properly. The mattress itself is 120 x 190cm, so measure your room against both figures, particularly in box rooms and loft conversions where every centimetre counts.
How much wider is the small double than the single Medi Flex?
The UK small double is 30cm wider than the UK single, and both are the same 190cm length. That extra width matters most for a teenager or adult who has outgrown a single but whose room can't lose much floor space: you gain real stretching room while keeping the bed's footprint modest.
Is the small double a good size for a rental or holiday let?
It's a sensible fit for small second bedrooms. The 4ft width sleeps one guest generously or two at a squeeze, and the waterproof cover and Source 5 fire rating suit settings where compliance and easy cleaning matter. If the room takes a bigger bed comfortably, the UK double gives sharing guests noticeably more space.
Will the small double Medi Flex fit a standard 4ft bed frame?
Yes. The UK small double is a standard British size at 120 x 190cm, so 4ft frames, divan bases and small double fitted sheets are all easy to find. Pair it with a standard double duvet, which drapes better over a 4ft mattress than small double bedding alone.