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.
- The traditional couples' footprint: At 135 x 190cm, or 4ft 6in x 6ft 3in, this is the size most UK bedrooms were furnished around, so frames and bases are easy to find.
- Room for two at this price point: You get 67.5cm each for two people sharing, which pairs sensibly with a mattress aimed at value rather than premium spend.
- Weight-responsive support for two different bodies: The PostureTech CS springs firm up under heavier pressure, which means each of you gets support matched to your own weight rather than a compromise.
- Fits where a king wouldn't: The UK king needs at least 2.7m x 2.9m by our guidance; the UK double asks only 2.6m x 2.8m, often the difference between having bedside tables or not.
- Easy to dress cheaply: Double sheets and 200 x 200cm duvets are sold everywhere at every price, useful if you're furnishing a whole home and the budget is already stretched.
This size suits you if...
You're a couple in a typical UK bedroom where a double leaves space to open the wardrobe and fit a table each side of the bed, or you're kitting out a first flat or a second bedroom where the bed has to share the floor with a wardrobe and a chest of drawers. It also suits a guest room that regularly hosts visiting couples without swallowing the space.
Consider another size if...
You and your partner both want more personal space and your room measures at least 2.7m x 2.9m. In that case we'd recommend the UK king instead: it's 15cm wider and 10cm longer than the UK double.
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Is a UK double Sealy Advantage Classic big enough for a couple?
For most couples, yes: it's the long-standing UK standard for two, giving 67.5cm each for two people sharing. One caveat with this particular mattress is its open coil system, which transfers movement more than pocket springs, so at this width light sleepers may notice a partner turning over during the night.
What room size do I need for the Sealy Advantage Classic double?
We suggest allowing at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That's our guidance rather than Sealy's, and it assumes you want to walk around the bed and open drawers without shuffling sideways. Tighter rooms can work if storage sits elsewhere.
Should I get the Sealy Advantage Classic in a double or a king?
It comes down to your room. The UK double is 15cm narrower and 10cm shorter than the UK king, and for the UK king we suggest at least 2.7m x 2.9m. If your bedroom clears that with space for bedside tables on both sides, the extra width is a real comfort gain for couples; if not, the UK double is the safer buy.
Will the double fit up the stairs in an older house?
At 135 x 190cm it's one of the easier shared sizes to manoeuvre, and the sprung construction means it can be tilted on its side for turning stairs in older terraces or tight new build landings. It doesn't arrive rolled, though, so measure your stairwell and doorways before ordering.
Where can I buy the Sealy Advantage Classic in a double?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them, so what you see reflects current stock rather than a snapshot. It's a UK double, 135 x 190cm, so standard double bed frames, divan bases and bedding all fit without any special ordering.