Rest Assured Kelbrook Double Mattress
The Rest Assured Kelbrook is an extra firm pocket spring mattress built around 1400 pocket springs, which means each spring moves independently, so you get support that follows your shape rather than one solid push-back.
- Extra-firm for back & front sleepers
- Wool fillings help you stay cool
- Minimises partner disturbance
£609
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Rest Assured Kelbrook Mattress
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Mattress details
Mattress
Rest Assured Kelbrook Mattress
Size
Firmness
Extra Firm
Construction
Pocket Spring
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.
Key benefits
- Room to share, room to move: At 67.5cm each for two people sharing, the UK double keeps you close, and the independently sewn springs stop most of your partner's movement reaching your side.
- Fits the rooms most people have: We suggest at least 2.6m x 2.8m for a UK double, so it suits a typical master bedroom or a decent second bedroom where a king would crowd the floor.
- Space left for bedside tables: Because the UK double is 15cm narrower than the UK king, you're more likely to keep a bedside table on each side, which couples tend to miss quickly once it's gone.
- Firm support for two back or front sleepers: If you both sleep on your back or front, the extra firm feel holds you level, although a side sleeper sharing with you may find their shoulder has too little give.
- Wool helps when two share the heat: Two bodies on a UK double warm the bed faster, and the wool fillings over the springs breathe better than synthetic layers, so the surface stays a little cooler.
This size suits you if...
You share the bed with a partner who, like you, prefers a solid feel on your back or front, and your bedroom has space for the bed plus furniture on both sides. It also fits a guest room where visiting couples stay for a night or two.
Consider another size if...
Either of you is tall, or you find 67.5cm each too close for a good night. We'd recommend the UK king instead, which is 10cm longer, provided your room is at least 2.7m x 2.9m.
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FAQ's
How much space does each person get on a Kelbrook double?
Two people sharing a Kelbrook in a UK double get 67.5cm each. That's snug rather than roomy, so the pocket springs are helpful here: each one compresses on its own, which keeps most of a partner's shifting on their half of the bed rather than rolling across to yours.
Will a Rest Assured Kelbrook double fit my bedroom with bedside tables?
We suggest allowing at least 2.6m x 2.8m for a UK double, with around 3m x 3m the more comfortable norm. Near the minimum you'll have a bed and walkway, but bedside tables on both sides get tight. Nearer 3m x 3m, there's usually room for tables and a wardrobe too.
What are the Kelbrook double mattress dimensions in feet?
The Kelbrook in a UK double measures 4ft 6in x 6ft 3in, which is 135 x 190cm. That's the standard British double footprint, so it should drop into an existing double bed frame, and ordinary double sheets will fit.
Kelbrook double or king for a tall couple?
The UK king is 10cm longer than the UK double and gives 75cm each, so 7.5cm more per person. If either of you touches the footboard on a 190cm bed, the extra length is the reason to size up. We suggest at least 2.7m x 2.9m for the UK king.
Is the Kelbrook in a UK double a good pick for a guest room?
The UK double width works well when couples visit, and it fits smaller spare rooms than a king would. The catch is the extra firm feel: guests who sleep on their side may find it too unyielding at the hip and shoulder, so it suits a household whose regular visitors prefer firm beds.