Sealy PosturePedic Merivale Combination Super King Mattress
The Sealy PosturePedic Merivale Combination Mattress uses INFUSE Black Diamond Graphite foam to draw heat away from the body, which means you should sleep cooler on a medium-firm surface.
- Stays cooler through the night
- Eases pressure at hips & lower back
- Cover endorsed by Allergy UK
£2,999
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Sealy PosturePedic Merivale Combination Mattress
More available sizes
Mattress details
Mattress
Sealy PosturePedic Merivale Combination Mattress
Size
Firmness
Medium Firm
Construction
Foam
Open Coil Spring
Depth (cm)
33
Layers
5
Layer Details
EternityFibre surface
A soft EternityFibre surface that keeps the mattress feeling fresh, so it should feel pleasant to settle onto.
INFUSE Black Diamond Graphite foam
A cooling foam that draws heat away from the body, which helps you stay more comfortable if you sleep warm.
INFUSE Eco ComfortCore foam
A plant-based foam that targets pressure relief at the hips and lower back, so those areas feel cushioned.
AlignSupport Coil system
Patented coils that give deep-down, responsive support, so the mattress moves with you and holds you steady.
BasePlank foundation
A foundation with two layers of durable foam that adds stability and strength to the whole mattress.
Layer details from crushedvelvetbedstore.co.uk product page, October 2026.
Key benefits
- Distance from a restless partner: With 90cm each for two sharing, a partner who shifts position all night is far enough away that you're much less likely to feel every turn.
- More width than a UK king: Compared with the UK king you get 15cm more each at the same length, so all the extra room goes sideways, where couples usually run short.
- Room when the family piles in: When a small child or a large dog joins you as a matter of routine, the width means two adults aren't left clinging to the outer edges.
- Edges you will actually use: The UniCased edge system should keep the sides dependable, which matters more on a bed this wide because someone usually ends up sleeping near one.
- Help with shared body heat: More bodies in one bed means more warmth, and the graphite foam is designed to draw heat away so a crowded night feels a little less stuffy.
- In proportion in a large room: In a generous master bedroom or a high-ceilinged period room, a UK super king fills the floor sensibly where a UK king can look slightly undersized.
This size suits you if...
You share with a partner whose movement regularly wakes you, children or a big dog often end up in the bed, and your bedroom measures at least 3m x 2.9m, our suggested minimum.
Consider another size if...
Your bedroom is smaller than 3m x 2.9m or your landing has a tight turn. We'd recommend the UK king instead, which needs at least 2.7m x 2.9m.
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FAQ's
What size bedroom do I need for a Sealy Merivale UK super king?
We suggest at least 3m x 2.9m for a UK super king, with around 3.5m x 3.2m feeling comfortable. That leaves space to walk round both sides and open wardrobe doors. If your room falls short, the UK king needs at least 2.7m x 2.9m and keeps the same 200cm length.
How much space does each person get on a UK super king Merivale?
Two people sharing get 90cm each. That's 15cm more each than the UK king and 22.5cm more each than the UK double. For a couple where one person moves a lot, that extra distance does more to protect your sleep than any comfort layer could.
Is a UK super king big enough for two adults and a child?
For a small child who wanders in during the night, yes, in most cases. The 180cm width leaves enough room that neither adult gets pushed right to the side, and the UniCased edges should feel steady if you do end up near one. Regular three-person nights with an older child will still feel snug.
What bedding fits the Merivale in a UK super king?
You'll need UK super king sheets and a 260 x 220cm duvet. The Merivale is 33cm deep, so choose fitted sheets sold for deep mattresses, as shallow pockets tend to pop off the corners. Super king bedding also costs a little more than UK king, so factor that in.
Will a UK super king mattress fit through my house?
At 180 x 200cm and 33cm deep it's a bulky item to carry, so measure before you order. Check how far the bedroom door opens, any tight corner on the landing, and the ceiling height on loft conversion stairs. Once you're happy it will go up, compare the retailers listed on this page.