Rest Assured Kelbrook Mattress
Mattress
Rest Assured Kelbrook Mattress
Size
Firmness
Extra Firm
Construction
Depth (cm)
Layers
2
Layer Details
- Pocket springs. A core of 1400 pocket springs, each sewn into its own fabric pocket so it compresses independently. In practice this means support that adjusts to where you place weight, and less motion transferring across the bed.
- Wool fillings. Wool fillings sit above the spring unit, softening the surface slightly without undermining the extra firm feel. Wool also wicks moisture and breathes well, which helps if you tend to overheat at night.
Layer details from mattressman.co.uk product page, September 2026.
- Room to spread out on your own: Being 30cm wider than the UK single, it lets one adult lie starfish or change position freely, which suits restless back and front sleepers.
- Fits tighter double rooms: It is 15cm narrower than the UK double, which can decide whether a bedroom door swings clear of the frame or catches on it.
- Copes with a guest couple: The independent pocket springs limit how far one person's movement travels, which helps when two people share the UK small double for a weekend.
- Breathable in a smaller room: Wool fillings breathe well, which helps in a box room or loft conversion where the air can feel slightly close by morning.
- Easy to dress and frame: As a standard 4ft UK size, small double frames and fitted sheets are easy to find, so the Kelbrook should slot into furniture you already own.
This size suits you if...
You sleep alone and want more room than a UK single gives, your double bedroom is too tight for a UK double to leave a clear walkway, or a partner stays over only now and then and you both like a firm, supportive surface.
Consider another size if...
Two of you share the bed every night and both want room to move. We'd recommend the UK double instead, and we suggest at least 2.6m x 2.8m of room for it.
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Will a Rest Assured Kelbrook small double fit in a box room?
We suggest a room of at least 2.4m x 2.8m for the UK small double. At 120 x 190cm, it leaves more floor free than the UK double, which is 15cm wider, so it often suits a box room where a door or wardrobe needs clearance. Measure the door swing before you order.
Is the Kelbrook small double big enough for two people every night?
For the odd weekend, yes, and the pocket springs help stop one person's movement reaching the other. For nightly sharing we'd point you to the UK double, which gives 67.5cm each for two sharing, or the UK king at 75cm each. An extra firm surface does little to ease a tight squeeze.
How much wider is a Kelbrook small double than a single?
The UK small double is 30cm wider than the UK single, and both are the same length. That extra width lets a solo sleeper on the Kelbrook roll over or lie spread out. By our guidance, the UK single needs a room of at least 2.1m x 2.8m.
Kelbrook small double or king for a loft conversion?
In a loft conversion with sloping ceilings, standing room beside the bed is often the real limit. The UK small double is 30cm narrower and 10cm shorter than the UK king. We suggest at least 2.7m x 2.9m for the UK king, against 2.4m x 2.8m for the UK small double.
Is a 4ft Kelbrook good for a teenager outgrowing a single?
It can be, if they sleep on their back or front, because the extra firm surface is less forgiving for lighter side sleepers. The 4ft x 6ft 3in footprint gives them 30cm more width than the UK single without taking as much floor as the UK double.