Sealy Waltham Latex Advantage Small Double Mattress
The Sealy Waltham Latex Advantage pairs a natural latex comfort layer with Sealy's PostureTech Core Support Springs, which means you get the adaptive, body-hugging feel of latex over a supportive sprung base.
- Pressure relief without feeling stuck
- Sleeps cooler than memory foam
- Firmer support under your hips
£558
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Sealy Waltham Latex Advantage Mattress
More available sizes
Mattress details
Mattress
Sealy Waltham Latex Advantage Mattress
Size
Firmness
Medium Firm
Construction
Latex
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.
Key benefits
- Real room for one: At 120 x 190cm you get 30cm more width than a UK single, so you can shift position freely without the latex layer ending at your elbow.
- Fits where a double will not: The UK small double is 15cm narrower than the UK double, which is often the difference between a door that clears the bed frame and one that scrapes it.
- Latex without the sink: The natural latex layer shapes to you then springs back, so moving around a narrower mattress feels easy rather than effortful.
- Steady support at 4ft: Sealy's PostureTech Core Support Springs vary in tension, meaning your hips get firmer resistance than your shoulders even on this compact footprint.
- Easy to dress: 4ft is a standard UK size, so small double fitted sheets are simple to find and a standard double duvet drapes generously over it.
This size suits you if...
You sleep alone every night and have grown tired of the tight margins of a UK single, or your bedroom, loft conversion or studio simply cannot take a UK double without losing walking space, or you're furnishing a guest room where couples stay occasionally rather than nightly and a medium firm latex feel will suit most visitors.
Consider another size if...
You share the bed every night, because 120cm across two adults leaves little room to move on a medium firm surface. We'd recommend the UK double instead, allowing at least 2.6m x 2.8m of floor space.
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FAQ's
Is a small double Sealy Waltham big enough for a couple?
For the odd night, yes. The 120cm width is fine for guests staying occasionally, and latex makes shifting position easier than memory foam when space is tight. For nightly sharing we'd point you to the UK double, which is 15cm wider at the same length.
What room size do I need for the Sealy Waltham in a UK small double?
We suggest at least 2.4m x 2.8m. That leaves enough clearance to walk around the bed and open drawers. If your room comfortably exceeds that, it may take a UK double, for which we'd allow at least 2.6m x 2.8m.
How much wider is the small double than the single Sealy Waltham?
The UK small double is 30cm wider than the UK single, and the two are the same length at 190cm. That extra width is the whole point of this size: a solo sleeper gets genuine room to spread out without moving up to a double footprint.
Will the small double fit in a loft conversion or box room?
Often, yes, and that's where this size does its best work. At 4ft x 6ft 3in it can leave standing room beside the bed where a UK double would not. Measure your usable floor space against our suggested minimum of 2.4m x 2.8m before ordering.
Where can I buy the Sealy Waltham in a small double?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them. Because the UK small double is a standard 4ft size, frames and bedding are easy to source separately, with small double fitted sheets and a standard double duvet.