Sealy Waltham Latex Advantage Mattress
Mattress
Sealy Waltham Latex Advantage Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
29
Layers
3
Layer Details
- Quilted sleep surface. A plush quilted top adds the final touch of comfort. This gives the mattress a softer initial feel before you reach the firmer layers below.
- Latex. A plush, adaptive material that responds to your body shape for individualised comfort. It contours without the slow sink of memory foam, which means easier movement and a cooler sleep.
- PostureTech Core Support Springs. Sealy's own spring design uses unique shapes and varied tension to deliver full-body support and pressure relief. In practice this means firmer resistance where you carry more weight, so your spine stays better aligned.
Layer details from mattressonline.co.uk product page, September 2026.
- A grown-up mattress in a compact size: Latex over PostureTech springs is unusual at 90cm wide, which means a child or teen gets the same adaptive support an adult would.
- Fits the smallest rooms: At 3ft x 6ft 3in it leaves floor space free for a desk, wardrobe or toy storage in a squeezed child's room.
- Medium firm suits growing sleepers: The firmer feel keeps spines aligned as teenagers grow, with the quilted top softening that first contact.
- Cooler for single sleepers: Latex sleeps cooler than memory foam, useful in box rooms and loft spaces where heat gathers.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm duvet fit, and both are the most widely stocked bedding of any size.
This size suits you if...
You're buying for a child or teenager and want something supportive enough to last through growth spurts, you sleep alone and your room can't take anything wider than 3ft, or you're kitting out a spare room or a room that doubles as an office where the bed has to share space. It also suits a student moving into a first flat where the frame is provided but the mattress isn't.
Consider another size if...
You're an adult who moves around a lot in the night, as 90cm can feel restrictive. The Sealy Waltham in a UK small double gives you 30cm more width at the same length; allow at least 2.4m x 2.8m for it.
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Is the Sealy Waltham UK single a good mattress for a child?
Yes, with one caveat. The latex and spring construction supports a growing spine well, and latex sleeps cooler than foam, which children tend to appreciate. The medium firm feel may seem a touch solid to a very light child at first, though the quilted top softens the surface. It's a mattress a child won't outgrow in feel, only in height.
Will the Sealy Waltham UK single fit a bunk bed or mid sleeper?
The footprint fits: 90 x 190cm is the standard bunk size. Depth is the thing to check. This mattress is 29cm deep, which is taller than many raised frames allow, especially top bunks where the guard rail needs to sit well above the mattress surface. Measure your frame's maximum mattress depth before ordering.
What room size do I need for the UK single Sealy Waltham?
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 practice a UK single fits almost any UK bedroom, including box rooms and loft conversions where the bed sits along one wall.
Is the Sealy Waltham single big enough for an adult?
For one adult, yes, provided you're a fairly settled sleeper. At 3ft wide you have the whole 90cm to yourself, and at 6ft 3in long it suits most heights. Restless sleepers or anyone used to sharing a double may find it narrow, in which case the UK small double adds 30cm of width.
Does the Sealy Waltham single work in a guest room?
Well, particularly where the room does double duty. Two UK singles suit a guest room better than one double when visitors aren't a couple, and the 90cm width leaves space for a desk if the room is also an office. The latex build means guests get genuine comfort rather than the thin spare-room standard.