Sealy Steeple Ortho Plus Mattress
Mattress
Sealy Steeple Ortho Plus Mattress
Size
Firmness
Extra Firm
Construction
Depth (cm)
29
Layers
2
Layer Details
- Comfort Layer. Soft White Fibres sit at the surface to add a touch of cosiness. They soften the first impression slightly, but this remains an extra firm mattress underneath.
- Support System. PostureTech Core Support Springs with zoned PowerPack technology do the real work here. The zoning firms up support through the lumbar region, which means your lower back stays level rather than dipping.
Layer details from mattressonline.co.uk product page, September 2026.
- 90cm each for two sharers: Two people get 90cm each across the 180cm width, which means a restless partner can turn all night without pulling you awake.
- Firm support across the full width: The zoned PostureTech Core Support Springs keep the lumbar region reinforced, so your lower back stays level even on a surface this wide.
- Room for the whole household: When children or a large dog treat your bed as theirs, this size means the adults still get a fair share of the surface.
- Full 200cm length: At 6ft 6in long, taller sleepers get the same generous length as a UK king, with an extra 30cm of width on top.
- Distance beats any comfort layer: Extra firm mattresses transfer less wobble than soft ones, and the sheer width here adds physical separation, a useful pairing for light sleepers sharing a bed.
This size suits you if...
You share the bed every night and want the most sleeping space a standard UK size offers, your partner is restless enough that width matters more than any comfort feature, or children and pets regularly join you and everyone still needs room. You'll also need a bedroom of at least 3m x 2.9m and a genuine preference for an extra firm feel.
Consider another size if...
Your bedroom falls short of our suggested 3m x 2.9m minimum, or the bed would dominate the space. We'd recommend the UK king instead: it's 30cm narrower, the same length, and needs a smaller room, at least 2.7m x 2.9m by our guidance.
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Is the Sealy Steeple Ortho Plus super king big enough for a couple and a child?
It's the most forgiving standard size for it. At 180cm wide, two adults have 90cm each, so a small visitor squeezing in overnight leaves everyone workable space. The extra firm surface also means less bounce travelling across the mattress when someone climbs in, which helps whoever is still asleep stay that way.
Will the Sealy Steeple Ortho Plus in a UK super king fit in my bedroom?
We suggest a room of at least 3m x 2.9m for a UK super king, and around 3.5m x 3.2m feels more comfortable if you want bedside tables and easy walking space on both sides. Measure the door swing and any landing turns too, as a 180 x 200cm mattress is awkward to manoeuvre upstairs.
How much bigger is the super king than the UK king version of this mattress?
The UK super king is 30cm wider than the UK king, and the two are the same length at 200cm. That extra width is the whole argument for sizing up: it's the difference between feeling a partner turn over and barely noticing. The firmness, depth and construction are identical in both sizes.
Is a super king a good choice for a restless partner on an extra firm mattress?
Yes, and the combination works well. Firmer spring surfaces like this one tend to transmit less movement than soft, bouncy builds, and 90cm each of width adds real distance between you. If disturbed sleep is the reason you're upgrading, the UK super king is the size that solves it most directly.
Where can I compare prices for the Sealy Steeple Ortho Plus super king?
Use the retailer table on this page. The prices shown here are updated as retailers change them, so it's a more reliable picture than any figure written into the text. Stock at this size can shift, so if you see it available at a price you're happy with, it's sensible to move fairly promptly.