Jay-Be Flex Ultra Firm Single Mattress
The Jay-Be Flex Ultra Firm is a hybrid mattress built for people who want a genuinely hard sleeping surface.
- Extra-firm, traditional sprung feel
- Breathable fibres reduce heat build-up
- Hypoallergenic, vegan-friendly fillings
£224.23
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Jay-Be Flex Ultra Firm Mattress
More available sizes
Mattress details
Mattress
Jay-Be Flex Ultra Firm Mattress
Size
Firmness
Firm
Construction
Foam
Hybrid
Rolled
Open Coil Spring
Depth (cm)
21
Layers
4
Layer Details
Advance e-Fibre
A breathable filling layer at the top of the mattress. It lets air move through the surface, which means less heat building up around you overnight.
Rebound e-Fibre
A second breathable filling layer beneath the surface. It sits between you and the springs, adding a little resilience without softening the extra firm feel.
High Density e-Fibre
A denser breathable filling layer above the spring core. This is where much of the firmness comes from, giving the surface its solid, supportive character.
Open coil spring core
A sprung core providing reliable support across the mattress, with 325 springs in the king size. Open coil systems move as one unit, which means a firmer, more traditional feel than pocket springs.
Layer details from furniturevillage.co.uk product page, September 2026.
Key benefits
- Fits raised frames: The 21cm depth sits well in bunk beds, cabin beds and mid sleepers, where a deeper mattress can ride too high against the frame.
- Compact footprint: At 90cm wide it leaves room for a desk, wardrobe or toy storage in a child's bedroom, or a walkway between two beds where siblings share.
- Firm support for one: An open coil core with dense e-Fibre layers on top, which means a solid, held feel for back and front sleepers rather than a cradling one.
- Breathable for small rooms: The e-Fibre fillings let air move through the surface, a help in box rooms and loft spaces where heat can build up overnight.
- Easy bedding: Standard single sheets and a 135 x 200cm duvet fit, the cheapest and most widely stocked bedding of any UK size.
This size suits you if...
You're buying for a child's or teenager's room where the bed shares floor space with a desk and storage, you need a slim mattress for a bunk or mid sleeper frame, or you're kitting out a spare room or study that occasionally hosts a guest and you specifically want a firm, breathable surface.
Consider another size if...
You share the bed, or you're a larger adult who finds 90cm restrictive on an already firm surface. We'd recommend the UK small double instead: 30cm wider, the same length, and it needs a room of at least 2.4m x 2.8m.
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FAQ's
Will the Jay-Be Flex Ultra Firm UK single fit a bunk bed?
It's a strong candidate. At 21cm deep it's slimmer than many hybrids, so it should sit at a sensible height in bunk, cabin and mid sleeper frames. Check your frame's maximum mattress depth before ordering, as some bunks specify a limit, but 21cm falls within what most raised frames accept.
Is the Jay-Be Flex Ultra Firm single suitable for a child?
The size is the UK standard for children's and teenagers' rooms, and the hypoallergenic e-Fibre fillings are a plus for young allergy sufferers. Bear in mind this is an extra firm surface, though. Lightweight side sleepers, which many children are, may find it hard on the shoulder and hip, so consider how your child sleeps first.
What room size do I need for a UK single mattress?
We suggest allowing at least 2.1m x 2.8m of floor space, which is our own guidance rather than Jay-Be's. That leaves enough clearance to move around the bed and open drawers or a wardrobe. Most UK box rooms and loft conversions can manage it, and the 90cm width keeps the footprint narrow under a sloped ceiling.
Is a single big enough for an adult on this mattress?
For one adult sleeping alone, yes, 90 x 190cm is the standard UK one-person size, and the extra firm surface suits back and front sleepers who like feeling held on top of the bed. If you're tall, note the UK king version is 10cm longer. Broad-shouldered adults may prefer the extra width of the UK small double.
Where can I buy the Jay-Be Flex Ultra Firm in a UK single?
Stock and pricing move around, so the most reliable answer is the live comparison table on this page. The prices shown here are updated as retailers change them, which makes it worth a quick check even if you've seen the mattress listed elsewhere, as the single is sometimes priced differently from the larger sizes.