Sealy Mellbreak Ortho Plus Mattress
Mattress
Sealy Mellbreak Ortho Plus Mattress
Size
Firmness
Construction
Depth (cm)
28
Layers
2
Layer Details
- Comfort Layer. Soft white synthetic fibres sit on top, which means a cosy surface feel rather than the boardy firmness you might expect from an ortho mattress. They're durable and resilient, so the layer should hold its shape rather than flattening quickly.
- Support System. PostureTech Core Support Springs use unique shapes and varied tension, which means the mattress responds differently to your hips than to your shoulders, giving full-body support with pressure relief where you need it. A PowerPack filling in the centre zone adds targeted lumbar support.
Layer details from mattressonline.co.uk product page, September 2026.
- Real space for two firm-mattress sleepers: With 75cm each for two people sharing, you both get proper room on a surface that supports rather than sinks.
- Firm support travels less across a wider bed: The PostureTech springs respond to each body separately, and the extra width means one partner turning over is felt less by the other.
- Extra length for taller sleepers: At 200cm long, the UK king is 10cm longer than the UK Double, which matters more than width if one of you keeps hitting the footboard.
- Suits partners on different schedules: If one of you gets up hours before the other, the wider footprint helps the early riser slip out with less disturbance on a firm, low-motion surface.
- Lumbar support in the middle of a shared bed: The PowerPack centre-zone filling sits where two sharers drift towards the middle, which means extra lower-back support exactly where a couple tends to need it.
- Live prices in one place: Compare the retailers listed on this page; the prices shown here are updated as retailers change them.
This size suits you if...
You share the bed every night and a double now feels cramped, especially if one of you is a restless sleeper or keeps early hours while the other sleeps in. It also makes sense if either partner is approaching six foot, since the 200cm length gives feet somewhere to go, or if you want firm orthopaedic-style support without giving up personal space.
Consider another size if...
Your bedroom is under our suggested minimum of 2.7m x 2.9m, or you sleep alone. We'd recommend the UK double instead, which needs a smaller room at 2.6m x 2.8m and still suits a solo sleeper generously.
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How big is the Sealy Mellbreak Ortho Plus in a UK king?
It measures 150 x 200cm, or 5ft x 6ft 6in, and is 28cm deep. That works out at 75cm each for two people sharing, and the 200cm length gives taller sleepers a little more room than the 190cm of a UK double.
Is the Sealy Mellbreak Ortho Plus UK king hard to flip?
It's double-sided, so regular flipping evens out wear, and across owner reviews this mattress is described as heavy. In a king that's a genuine two-person job, so if you live alone or have back trouble, plan on help or consider the smaller UK double, which is easier to handle.
What room size do I need for this mattress in a UK king?
We suggest at least 2.7m x 2.9m so you can walk round both sides and open drawers comfortably. A new build master bedroom can shrink quickly once fitted wardrobes go in, so measure the usable floor rather than the room on the plan.
Is a UK king worth it over a double for couples on a firm mattress?
Usually, yes. The UK king is 15cm wider and 10cm longer than the UK double, and on a firm mattress like this you don't roll towards each other, so the extra width becomes genuine personal space rather than dead middle ground.
Should I size up to the super king instead?
The UK super king is 30cm wider than the UK king and the same length, so it's about width, useful if a dog routinely claims part of the bed. It needs a room of at least 3m x 2.9m, though, so the UK king is the safer fit for most bedrooms.