Firmness
Extra Firm
Type
Pocket Spring
Depth (cm)
Number of Layers
2
Trial Period (nights)
60
Warranty (years)
Price Range
£465 to £720
Best Sleeping Position(s)
Certifications
Assessed from the specification published by Mattress Man, captured September 2026, and from regular price comparison across our UK retail partners.
Choose the Kelbrook if you sleep on your back or front and want firm, traditional support without a soft top layer getting in the way. The 1400 pocket springs respond to each sleeper separately, which means less disturbance if you share the bed and your partner moves about. Wool fillings are a genuine plus at this price, breathing better than synthetic alternatives, so if you tend to run warm it should stay a little more temperate than foam-heavy rivals. Starting at £465 for a Single, it sits at a reasonable price for a pocket-sprung, wool-filled build. If you buy through Mattressman, they list a 60-night trial and free next day delivery, though those are the retailer's terms, not Rest Assured's.
Key Features & what's inside
- 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.
Who's it NOT for?
This is an extra firm mattress, so it's not the one for side sleepers, who need more give at the shoulder and hip, or for lighter people who may simply sit on top of it rather than sink in. If you like a plush, cushioned surface, look elsewhere.
Rest Assured Kelbrook Mattress
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How firm is the Rest Assured Kelbrook mattress?
It's rated extra firm, the firmest end of the scale. That suits back and front sleepers who want a solid, supportive surface, but side sleepers and lighter people will likely find it too hard on pressure points like shoulders and hips.
How many springs does the Rest Assured Kelbrook have?
It has 1400 pocket springs. Each one sits in its own fabric pocket and moves independently, which means the mattress contours to your body and limits the motion you feel when a partner shifts position.
Does the Rest Assured Kelbrook come with a trial period?
Mattressman lists a 60-night trial on the Kelbrook. Bear in mind that's the retailer's own offer rather than a Rest Assured guarantee, so check the terms wherever you actually buy.
What sizes does the Rest Assured Kelbrook come in?
Five UK sizes: Single, Small Double, Double, King and Super King. Prices range from £465 to £720 depending on the size you choose.
How much does the Rest Assured Kelbrook cost?
Prices start from £465 and run up to £720 for the larger sizes. For a pocket-sprung mattress with natural wool fillings, that's a fair price, at the cost of a very firm feel that won't suit everyone.
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