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.
- A compact footprint with grown-up support: The PostureTech CS springs respond to body weight, which means a light child and a full-grown adult guest both get support where they press down.
- Wool comfort for growing sleepers: The wool filling gives a soft, cushioned surface without the sink of memory foam, a feel many children and teens settle into easily.
- Edge support matters more at 90cm wide: EdgeGuard high-density foam around the sides means the narrow width feels usable right to the edge, rather than leaving a no-go strip.
- Standard bedding, no hunting around: At 90 x 190cm it takes ordinary single sheets and a single duvet, the cheapest and most widely stocked bedding in the UK.
- Built to outlast childhood phases: The twice-tempered springs are treated to stay resilient, so the mattress should hold its support through years of a child's or guest room's use.
This size suits you if...
You're furnishing a child's or teenager's room where the bed shares space with a desk, wardrobe and toy storage, you're setting up a spare room that doubles as an office, or you sleep alone in a compact bedroom and want a natural-leaning sprung mattress without giving up floor space.
Consider another size if...
You're an adult who shares the bed, or a solo sleeper who likes to spread out. We'd recommend the UK double instead, which is 45cm wider; allow at least 2.6m x 2.8m of floor space for it.
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How big is the Sealy Advantage Topaz Natural in a UK single?
It measures 90 x 190cm, or 3ft x 6ft 3in. That is the standard UK one-person size, and we suggest a room of at least 2.1m x 2.8m so you have space to walk around and open drawers comfortably.
Will the UK single Sealy Advantage Topaz Natural fit a bunk or mid sleeper?
The width matches standard bunk and mid sleeper frames, but the 27cm depth needs checking. Many raised frames specify a maximum mattress depth so the guard rail stays high enough. Measure from the base to the top of the rail before buying, especially for younger children.
Is a UK single long enough for a teenager?
At 190cm long, the UK single is the same length as the UK double, so most teenagers have room to grow into it. Very tall teens may eventually want the UK king, which is 10cm longer, though that means a much bigger footprint in the room.
Should I get the UK single or the UK small double?
The UK single is 30cm narrower than the UK small double, and both are the same length. For a child's room or a tight guest room, the single leaves useful floor space. If a solo adult will sleep on it every night and the room allows at least 2.4m x 2.8m, the UK small double is the more comfortable choice.
Is the single size of this mattress good for a guest room?
Yes, particularly where the room does double duty as an office, since the 90cm width leaves space for a desk. The medium feel and responsive springs suit occasional guests of different weights, and the EdgeGuard foam keeps the narrow edge feeling stable. Compare the retailers listed on this page for the current price.