Harrison Spinks Canterbury 4450 Mattress
Mattress
Harrison Spinks Canterbury 4450 Mattress
Size
Firmness
Construction
Depth (cm)
27
Layers
3
Layer Details
- Cover. A breathable Belgian damask fabric cover. It lets air move through the sleep surface, which helps the natural fillings beneath do their temperature work.
- Comfort Fillings. Wool, Ecotex fibres, flax and sustainably sourced cotton. The wool gives a soft cushioned feel, the Ecotex fibres are made from 100% recyclable materials, and the flax and cotton are breathable, absorbent fibres that wick moisture away from you.
- Support System. 4450 pocket springs combined with micro posture springs. Each pocket spring sits in its own fabric pocket and works independently, while the smaller micro springs contour to the exact shape of your body.
Layer details from mattressnextday.co.uk product page, September 2026.
- Distance beats any comfort layer: With 90cm each for two people sharing, a partner who turns all night is simply further away, and no filling can match that.
- 4450 springs across a wider bed: The pocket springs and micro posture springs respond independently across the full 180cm width, which means one sleeper's movement barely reaches the other.
- Space when the household joins you: If children or a large dog treat your bed as theirs, the UK super king keeps a fair share for the adults who paid for it.
- Natural fillings suit shared heat: Two bodies generate more warmth than one, and the wool, flax and cotton fillings wick moisture rather than trapping it like foam.
- Fills a large master properly: In a period property or generous new build main bedroom, a UK king can look undersized, while the UK super king sits in proportion.
This size suits you if...
You share the bed every night and one of you is a restless sleeper, your children or pets regularly join you and a UK king no longer feels big enough, or you have a large master bedroom where a smaller mattress would look lost. Measure first: we suggest at least 3m x 2.9m for this size, and closer to 3.5m x 3.2m to walk around it comfortably.
Consider another size if...
Your bedroom falls short of our suggested 3m x 2.9m minimum, or your stairs and landing can't take a flat, one-piece mattress this wide. We'd recommend the UK king instead, which is 30cm narrower, the same length, and needs at least 2.7m x 2.9m.
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Will the Canterbury 4450 super king fit up my stairs?
This is the check that bites at this size. The Canterbury 4450 arrives flat, never rolled, so you're moving a 180 x 200cm, 27cm deep mattress in one piece. Measure your staircase width, any landing turns and the bedroom door swing before ordering. If the route is tight, the UK king is 30cm narrower and noticeably easier to manoeuvre.
Is a UK super king big enough for a family who co-sleep?
It's the most realistic standard size for it. With 90cm each for two adults, a child wandering in at night borrows space without leaving either parent clinging to an edge. The independent pocket springs also help here, since a small body climbing aboard disturbs the surface locally rather than across the whole bed.
What room size do I need for the Canterbury 4450 in a super king?
We suggest at least 3m x 2.9m as a working minimum, with around 3.5m x 3.2m feeling comfortable once you add bedside tables on both sides and space to make the bed. In a loft conversion, check the sloping ceiling too: the wall the bed takes may be decided for you at this width.
Does a super king help if my partner is a restless sleeper?
More than any construction feature, yes. At 180cm wide you each get 90cm, roughly a single bed's worth of personal territory, so tossing and turning happens further from you. The Canterbury 4450's pocket springs then reduce what little movement does travel across, since each spring compresses independently rather than rocking the whole surface.
Is the super king Canterbury 4450 worth it over the UK king?
If your room and budget allow, the extra 30cm of width is the difference between sharing comfortably and negotiating space, especially with children or a dog in the mix. Both sizes are the same length. If your bedroom is under our suggested 3m x 2.9m, though, the UK king is the sensible call. Compare the retailers listed on this page for current prices.