Sealy Advantage Topaz Natural Mattress
Mattress
Sealy Advantage Topaz Natural Mattress
Size
Firmness
Depth (cm)
27
Layers
3
Layer Details
- Quilted Cover. The cover and fillings are stitched together into a patterned comfort quilt. This gives a settled, traditional surface rather than a loose, removable top.
- Wool. A wool filling that adds a soft, cushioned feel. It suits sleepers who prefer natural materials and a classic sprung-mattress character.
- PostureTech CS Springs. These springs respond to your body weight, targeting support at the areas where pressure is applied, which means your heavier zones get held up rather than sagging. They are twice tempered, so the steel is treated to stay resilient over time.
Layer details from mattressnextday.co.uk product page, September 2026.
- Real stretching room for one: At 120cm wide, one sleeper gets space to shift, sprawl and change position without meeting the edge, a noticeable step up from a UK single.
- Fits rooms a double cannot: The UK small double is 15cm narrower than the UK double, which can be the difference between a door that clears and one that scrapes.
- Usable edges matter more at 4ft: EdgeGuard high-density foam around the sides means the full 120cm width is sleepable, which counts when there is less mattress to begin with.
- Responsive support at any position: PostureTech CS springs firm up where you press down hardest, so wherever you drift across the width, your hips and shoulders stay properly held.
- Easy bedding to find: 4ft is a standard UK size, so small double fitted sheets are widely stocked, and the 27cm depth sits within them without a struggle.
This size suits you if...
You sleep alone and have outgrown a single, perhaps a teenager whose room simply cannot give up the floor space a double demands. Or your bedroom, box room or loft conversion is tight enough that 15cm of width decides whether you can still walk round the bed. It also suits a guest room where couples stay occasionally, since two people can share for the odd night on a medium sprung build like this.
Consider another size if...
You share the bed every night, because 120cm is a squeeze for two long term. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m of room for it.
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Is a small double big enough for two adults every night?
For occasional stays, yes, and the springs' weight-responsive support handles two sleepers without one side collapsing. For nightly sharing, 120cm leaves each of you with less width than a UK single offers alone, so most couples find it a squeeze. If you share every night, the UK double or UK king is a better long-term buy.
Will the Sealy Advantage Topaz Natural small double fit in a box room?
Usually, yes. The mattress is 120 x 190cm, and we suggest a room of at least 2.4m x 2.8m so you can open the door, walk round the bed and get to a wardrobe. Measure your usable floor, not the room's listed size, since alcoves and radiators eat into it quickly.
How much wider is a small double than a single?
The UK small double is 30cm wider than the UK single, and both are the same 190cm length. That extra width is what turns a bed you fit into a bed you can spread out in, which is why it suits teenagers and solo adults who toss and turn. The footprint gain in the room is modest by comparison.
What bed frame does the Sealy Advantage Topaz Natural small double need?
A standard 4ft frame or divan. Small double is a recognised UK size, so frames are easy to find, though the selection is slimmer than for a UK double. Check the frame's internal dimensions match 120 x 190cm, as a loose fit lets the mattress shift and a tight one distorts the edges.
Is the small double good value compared with other sizes?
Pricing shifts, so compare the retailers listed on this page rather than relying on a quoted figure; the prices shown here are updated as retailers change them. Small doubles often sit close to double prices, so if your room takes the UK double comfortably, it can be a small step up in cost for 15cm more width.