Komfi Unity Comfort Double Mattress in a Box
The Komfi Unity Comfort is a mattress in a box, which means it arrives rolled and compressed for easier delivery and manoeuvring up the stairs.
- Handy for a spare room
- Covers smaller bed frames well
- Boxed for easy handling
£138.80
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Komfi Unity Comfort Mattress in a Box
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Mattress details
Mattress
Komfi Unity Comfort Mattress in a Box
Size
Firmness
Medium
Construction
Rolled
Depth (cm)
Layers
2
Layer Details
Reflex foam top layer
A 4cm layer of soft reflex foam sits at the top. It gives the surface a softer, cushioned feel, which suits the medium firmness overall.
Ecofoam base
A 10cm foundation of Ecofoam, a re-engineered foam that is 100% recycled. It forms the bulk of the mattress and supports the softer layer above, and it also gives a lower carbon footprint than standard foam.
Layer details from komfi.com and archerssleepcentre.co.uk product pages, October 2026.
Key benefits
- The traditional couples' size: At 135 x 190cm, the UK double is the long-established size for two people sharing, giving each of you 67.5cm of width.
- Fits most UK bedrooms: We suggest allowing at least 2.6m x 2.8m, which most double bedrooms manage with space left for bedside tables on both sides.
- A budget-friendly way to furnish: If you're kitting out a first flat or a whole house at once, this double keeps the bedroom spend modest without dropping below the shared size couples expect.
- Boxed delivery suits awkward access: The mattress arrives compressed in a box, so it will manage the narrow stairs of an older terrace far more easily than a rigid double would.
- Easy to dress cheaply: Double sheets and duvets are stocked everywhere at every price point, which matters if the budget is already stretched thin.
This size suits you if...
You're a couple in a typical UK bedroom and want the standard shared size without spending much, you're furnishing a first flat or guest room where visiting pairs need a proper bed for two, or you sleep alone and want space to spread out, perhaps with a dog or cat claiming a corner.
Consider another size if...
Your room is comfortably larger than the 2.6m x 2.8m we suggest and you'd both appreciate more space. We'd recommend the UK king instead, which is 15cm wider and 10cm longer; allow at least 2.7m x 2.9m for it.
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FAQ's
Is the Komfi Unity Comfort in a UK double big enough for two adults?
Yes, for most couples. The UK double measures 135 x 190cm, which works out at 67.5cm each for two people sharing. That's the traditional shared standard in Britain, although if either of you is broad-shouldered or a restless sleeper, the UK king offers 15cm more width and 10cm more length.
What room size do I need for the Komfi Unity Comfort double?
We suggest allowing at least 2.6m x 2.8m. That leaves walking space around the bed and, in most rooms, enough for bedside tables on both sides. If you're also fitting a wardrobe and drawers into a second bedroom or a first flat, measure carefully before deciding between this and the UK small double.
Will the boxed double fit up narrow stairs?
This is one of the format's real advantages. The mattress arrives rolled and compressed in a box, so it's far easier to get round the turning stairs of an older terrace or a tight new build landing than a full 135 x 190cm mattress would be. Once unboxed, it expands to full size, so unpack it in the bedroom.
Should I choose the double or the UK small double for a small room?
The UK double is 15cm wider than the UK small double, and both are the same length. If two of you share every night, that extra width is usually worth having. For a compact spare room or occasional guests, the UK small double needs a slightly smaller room: we suggest at least 2.4m x 2.8m for it.
Is the double a good choice for a guest room?
It's the safest guest size, since it comfortably accommodates visiting couples as well as solo guests, and double bedding is cheap and easy to find. At this mattress's price point it's a reasonable spare room pick, though full specifications aren't published, so check the retailer's listing on this page if materials matter to you.