Sealy Advantage Classic Mattress
Mattress
Sealy Advantage Classic Mattress
Size
Firmness
Construction
Depth (cm)
24
Layers
4
Layer Details
- Quilted Cover. The cover and fillings are stitched together into a patterned comfort quilt, which means the soft top layer stays put rather than shifting over time. It gives that traditional, gently cushioned surface feel.
- Zoned Foam. This layer targets key areas of your body and applies support where you need it most. In practice that means firmer backing under heavier zones like your hips, with a little more give elsewhere.
- Reflex Foam. Reflex foam is a firmer, springier foam used here between the comfort layers and the springs. It adds a stable, comfortably supportive middle so you don't feel the coils directly.
- PostureTech CS Springs. These open coil springs are weight responsive, getting firmer as pressure increases, which means deeper support under the parts of you that need it. Sealy describes this as deep down support that's designed to last.
Layer details from mattressnextday.co.uk product page, September 2026.
- Fits compact rooms: At 90cm wide it slots into small bedrooms and loft conversions; allow at least 2.1m x 2.8m of floor space and you'll still have a walkway.
- A medium feel that grows with them: The PostureTech CS springs firm up as weight increases, which means the same mattress supports a child now and a heavier teenager later.
- Suits raised frames: The UK single is the standard size for bunks, cabin beds and mid sleepers, though check your frame's maximum mattress depth against this one's 24cm before buying.
- Guest-ready without fuss: In a spare room that doubles as an office, or a guest room with two beds, the single leaves space for the room's other job.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm single duvet fit, and both are the most widely stocked bedding of any UK size.
This size suits you if...
You're buying for a child or teenager moving into their first full-size bed, you sleep alone in a smaller room where every centimetre of floor matters, or you're kitting out a guest room or student flat where a dependable medium sprung mattress is all the brief asks for.
Consider another size if...
You're an adult who spreads out at night, or two of you will ever share it. The UK double of this mattress is 45cm wider at the same length; allow at least 2.6m x 2.8m of floor space for it.
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Is the Sealy Advantage Classic UK single big enough for an adult?
For one average-sized adult, yes. At 90 x 190cm (3ft x 6ft 3in) it's the standard UK one-person size, and the springs firm up under heavier areas, so adult weight is handled fine. Taller sleepers should note the UK king and super king versions are 10cm longer, although both need considerably more floor space.
Will the Sealy Advantage Classic single fit a bunk bed or mid sleeper?
The width and length match standard UK bunk and mid-sleeper frames, so the footprint fits. The thing to check is depth: this mattress is 24cm deep, and many raised frames set a maximum so the guard rail stays high enough. Compare that figure against your frame's guidance before ordering.
What room size do I need for a UK single mattress?
We suggest at least 2.1m x 2.8m of floor space, which is our own guidance rather than Sealy's. That allows room to walk alongside the bed and open drawers or a wardrobe. In a child's room competing with a desk and toy storage, the single's 90cm width is what keeps everything workable.
Is the Sealy Advantage Classic single a good first big bed for a child?
It's well suited to it. The medium feel with zoned foam gives gentle cushioning, and the weight-responsive springs mean it won't feel too soft as your child grows. Some owners report it slightly firmer than the medium label suggests, which for a growing child is generally a safe direction to err in.
Can I put two Sealy Advantage Classic singles in one guest room?
Often, yes. Two singles at 90cm each need less combined width than you might expect, and the arrangement suits guests who aren't a couple, siblings sharing, or a spare room that hosts varying visitors. Measure for a walkway between the beds, and compare the retailers listed on this page for each mattress.