MattressNextDay Medi Flex Waterproof Contract 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
- Room for two sharing: At 135 x 190cm, the UK double gives 67.5cm each for two people sharing, enough for a visiting couple in a guest room.
- Fits typical UK bedrooms: We suggest a room of at least 2.6m x 2.8m, which most second bedrooms and rental doubles can manage with furniture on both sides.
- Waterproof where it matters most: A shared size sees more spills and accidents, and the breathable waterproof cover wipes clean rather than soaking through to the foam.
- Easy to dress on a budget: Standard double sheets and a 200 x 200cm duvet are stocked everywhere, useful if you're kitting out several rooms at once.
- Light on stairs: A 14cm foam design in a double is far easier to manoeuvre up a tight terrace staircase or new build landing than a sprung mattress.
This size suits you if...
You're furnishing a rental, guest room or care setting and need a double that copes with moisture without a separate protector. It also fits if you're setting up a whole property on a tight budget and want the size most tenants and visiting couples expect, in a room of at least 2.6m x 2.8m.
Consider another size if...
You're buying for one person in a smaller room, such as a child's bedroom or compact rental single. We'd recommend the UK single instead: it's 45cm narrower, the same length, and we suggest a room of just 2.1m x 2.8m.
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FAQ's
Is the Medi Flex UK double big enough for a couple?
For occasional use, yes. The UK double gives 67.5cm each for two people sharing, which suits a guest room or short-term let comfortably. For a couple sleeping on it every night, the firm 14cm foam design is a little spartan, so we'd only suggest it where the waterproofing genuinely matters.
What room size do I need for the Medi Flex in a UK double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That leaves space for a wardrobe and drawers, and in most rooms enough clearance for bedside tables on both sides, which visiting couples and tenants tend to expect.
Should landlords choose the UK double or the UK small double?
The UK double is 15cm wider than the UK small double, and both are the same length. If the room allows it, the UK double is the safer choice for lettings because two sharing get more space and standard double bedding fits. In a genuinely tight room, we suggest at least 2.4m x 2.8m for the UK small double.
Is a double foam mattress easy to get upstairs?
Easier than most. The Medi Flex is a 14cm all-foam design, so a UK double is lighter and more forgiving on turning stairs in older terraces or tight new build landings than a sprung mattress of the same size. Two people can carry it comfortably.
Where can I buy the Medi Flex double at the best price?
Prices change often at this end of the market, so compare the retailers listed on this page. The prices shown here are updated as retailers change them, which means you're seeing current figures rather than a quote that's gone stale.