Sealy Tranquility Mattress
Mattress
Sealy Tranquility Mattress
Size
Firmness
Extra Firm
Construction
Depth (cm)
Layers
Layer Details
- Space to sleep on different schedules: With 75cm each for two people sharing, one of you can slip out for an early start with less chance of waking the other.
- Extra length for taller sleepers: At 200cm long, the UK king adds 10cm over the UK double, a genuine relief if one of you is approaching six foot.
- A firm surface across a wider bed: Sealy's AlignSupport spring system keeps that extra firm feel consistent, so neither sleeper drifts towards a softer patch in the middle.
- Easier getting in and out: An extra firm surface gives you something solid to push against, helpful if you're recovering from injury or surgery and every movement counts.
- Fits more rooms than a super king: We suggest at least 2.7m x 2.9m for a UK king, a more realistic ask for most UK bedrooms than the step up in size.
This size suits you if...
You share the bed and have outgrown the squeeze of a UK double, you both prefer a firm, supportive feel rather than a soft one, or one of you is tall enough that the extra 10cm of length matters as much as the width. It also suits couples on mismatched schedules who want to come and go with less disturbance.
Consider another size if...
Your room falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case we'd recommend the UK double instead, which needs a slightly smaller room at 2.6m x 2.8m.
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How big is the Sealy Tranquility in a UK king?
The UK king measures 150 x 200cm, or 5ft x 6ft 6in. For two people sharing, that gives you 75cm each. It's 15cm wider and 10cm longer than the UK double, so you gain space in both directions, useful if one of you is tall or you tend to spread out.
Is a UK king big enough for a couple on an extra firm mattress?
Yes, for most couples. At 75cm each for two people sharing, you both have room to settle into your own position, and the Tranquility's extra firm feel stays consistent across the width thanks to Sealy's AlignSupport spring system. Very restless sleepers, or couples sharing with a dog every night, may still prefer the UK super king.
What room size do I need for the Sealy Tranquility UK king?
We suggest at least 2.7m x 2.9m. That allows you to walk round the bed and open drawers without shuffling sideways. New build master bedrooms can feel tighter than the floor plan suggests once fitted wardrobes go in, so measure the usable floor space rather than the room itself before committing.
Should I get the Sealy Tranquility in a UK king or UK super king?
The UK king is 30cm narrower than the UK super king; both are the same 200cm length. If a pet routinely shares the bed or you both sprawl, the extra width helps, but we suggest at least 3m x 2.9m of room for the UK super king. For most couples upgrading from a UK double, the UK king is the sensible step.
Is the extra length of a UK king worth it for a tall sleeper?
Often, yes. The UK king is 10cm longer than the UK double as well as 15cm wider, and for anyone around six foot that length stops feet hanging off the end. On an extra firm mattress like the Tranquility, where you lie on the surface rather than sinking in, having your whole body supported matters slightly more.