Harrison Spinks Canterbury 4450 Mattress
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Mattress
Harrison Spinks Canterbury 4450 Mattress
Size
Firmness
Medium Firm
Construction
Foam
Pocket Spring
Rolled
Wool
Natural
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.
- Fits a compact room: At 90cm wide it leaves floor space free for a desk, wardrobe or toy storage, which matters in a child's bedroom already fighting for space.
- Natural fillings for growing sleepers: Wool, flax and cotton breathe and wick moisture, which means a child or teen sleeps cooler than they would on synthetic foam.
- Two singles for a guest room: The narrow footprint makes it practical to fit two beds in a spare room, giving guests flexibility a single double can't.
- Support that adjusts, even for lighter bodies: Micro posture springs contour to the sleeper's shape, so a lighter teenager still gets some give from the medium firm surface.
- Standard bedding, easily found: A UK single takes the cheapest and most widely stocked sheets and duvets of any size, useful when children go through bedding quickly.
- Check the depth on raised frames: At 27cm this is deeper than many bunk or mid-sleeper mattresses, so measure your frame's guard rail height before buying.
This size suits you if...
You're buying for a child or teenager and want natural, breathable fillings rather than foam, you need a proper mattress for a spare room or a room that doubles as an office, or you're a single adult in a compact bedroom, a loft conversion or a first flat where a 90cm footprint is the only one that works.
Consider another size if...
You're an adult who finds 90cm restrictive, or you tend to spread out in your sleep. The UK small double is 30cm wider and the same length, and we suggest at least 2.4m x 2.8m of floor space for it.
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Will the Harrison Spinks Canterbury 4450 UK single fit a bunk bed?
Be careful here. At 27cm deep, the Canterbury 4450 is deeper than many bunk and mid-sleeper frames allow, because the mattress must sit low enough for the guard rail to do its job. Measure from the base of your frame to the top of the rail before you buy, and check the frame maker's maximum mattress depth.
Is the Canterbury 4450 in a UK single good for a child or teenager?
It's a strong fit for this use. The wool, flax and cotton fillings breathe well, which suits children who sleep hot, and the micro posture springs adapt to lighter bodies. The medium firm feel may seem slightly firm to a very light side sleeper at first, but it gives growing backs consistent support.
What room size do I need for a UK single Canterbury 4450?
We suggest allowing at least 2.1m x 2.8m of floor space for a UK single, which is our own guidance rather than the manufacturer's. That leaves room to walk around the bed and open drawers. In a loft conversion, remember to check headroom where the bed sits, since sloped ceilings shrink usable space quickly.
How much bigger is a UK double than a UK single?
The UK single is 45cm narrower than the UK double, and the two are the same length. If you're weighing up the jump, the deciding factor is usually the room: we suggest at least 2.6m x 2.8m for the UK double, against 2.1m x 2.8m for the UK single.
Is a UK single long enough for a tall teenager?
A UK single is 190cm long, which suits most teenagers comfortably. If yours is unusually tall or still growing fast, the UK king is 10cm longer, although it's also 60cm wider and needs a room of at least 2.7m x 2.9m by our guidance, so it's a big step up in footprint.