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 footprint most bedrooms can take: At 135 x 190cm, this size leaves space for a wardrobe and drawers in a typical UK room, which the wider sizes often don't.
- Room for bedside tables on both sides: Allow at least 2.6m x 2.8m and most couples can still fit a table each, so nobody's phone charges on the floor.
- Latex handles two sleepers well: Latex responds quickly to movement rather than slowly sinking, which means one person shifting position is less likely to disturb the other.
- Sensible for a first flat or second bedroom: If you're furnishing a whole home at once, the UK double keeps the bed proportionate to the room and the bedding cheap to replace.
- Easy shared support: The PostureTech springs give firmer resistance under heavier areas, so two sleepers of different builds each get support suited to their weight.
This size suits you if...
You share the bed every night and your room sits around the typical UK size, or you sleep alone and want space to stretch without the bed dominating the floor plan. It also makes sense for a guest room that hosts visiting couples, since 135 x 190cm handles two sleepers while leaving space for the rest of the furniture.
Consider another size if...
You and your partner both like to sprawl, or one of you is a restless sleeper who drifts across the bed. With 67.5cm each for two people sharing, we'd recommend the UK king instead, allowing at least 2.7m x 2.9m of room.
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How big is the Sealy Waltham Latex Advantage in a UK double?
The UK double measures 135 x 190cm, which is 4ft 6in x 6ft 3in. It's the long-standing standard for two people sharing in the UK, and the same 29cm depth applies across every size of this mattress, so standard double fitted sheets with a deep enough wall will work.
Is the UK double Sealy Waltham big enough for two people?
It gives 67.5cm each for two people sharing. That works well for couples who sleep fairly close or settled, and the latex surface helps here, since it responds quickly when one of you moves rather than transferring every wriggle. Taller or broader couples may find the UK king a better long-term fit.
What size room do I need for the Sealy Waltham double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That allows you to open drawers, walk round both sides and keep bedside tables on both sides. If your room is tight but you still want to share, the UK small double is 15cm narrower and we suggest at least 2.4m x 2.8m for it.
How much smaller is the double than the king in this mattress?
The UK double is 15cm narrower and 10cm shorter than the UK king. That extra width matters most for couples who spread out; the extra length matters if either of you is around 6ft or taller, since the UK double is 6ft 3in long. For the UK king, allow at least 2.7m x 2.9m of room.
Is a double too big for one person?
Not at all. Plenty of solo sleepers choose the UK double for room to stretch, or because a dog or cat quietly claims a corner every night. The medium firm latex feel keeps you supported wherever you drift, and at 135cm wide it still fits a second bedroom or first flat without crowding it.