Feather & Black Belvoir Mattress
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Mattress
Feather & Black Belvoir Mattress
Size
Firmness
Firm
Construction
Foam
Pocket Spring
Memory Foam
Depth (cm)
28
Layers
3
Layer Details
Knitted pillowtop
A soft knitted pillowtop with a sumptuous pillow top finish, which adds extra depth. In practice this gives a cushioned first impression before you reach the firmer support below.
Memory foam
A layer of soothing memory foam that relieves pressure and works with the pocket springs beneath. It adapts to your movements during the night, so you get embracing support rather than a rigid feel.
Pocket springs
1,015 individually wrapped pocket springs in the king size. Each spring moves independently, which means support that follows your shape and less disturbance from a partner shifting about.
Layer details from featherandblack.com product page, September 2026.
- A shared size for average rooms: At 135 x 190cm, the UK double fits where the UK King would crowd the walls, leaving space for wardrobes and drawers.
- Bedside tables on both sides: In a room around the 2.6m x 2.8m minimum we suggest, a UK double usually still leaves enough width for a table each side.
- Less partner disturbance at this width: The pocket springs move independently, which matters at 67.5cm each: a partner turning over is felt less through the mattress.
- Firm support for two back or front sleepers: The firm tension holds both sleepers level rather than rolling you together, with the pillowtop softening the surface where hips press in.
- Easy to dress and to price up: Standard double sheets and duvets fit, and the retailer prices shown on this page update as they change.
This size suits you if...
You share the bed every night and your room comfortably clears our suggested 2.6m x 2.8m minimum, or you sleep alone and want space to spread out on a firm tension mattress. It also makes sense for a guest room that regularly hosts visiting couples, where the Belvoir's firm support suits a range of unknown sleepers better than something very soft would.
Consider another size if...
You and a partner both like room to sprawl, or one of you is a restless sleeper. The UK king is 15cm wider and 10cm longer; allow at least 2.7m x 2.9m and we'd recommend it instead.
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Is the Belvoir UK double big enough for a couple?
It gives two sharers 67.5cm each, which is the traditional couples' allowance in the UK. The Belvoir's pocket springs help here, since each spring moves independently and reduces the disturbance you feel from a partner shifting. Broad-shouldered couples, or anyone used to a hotel king, may still find the width a little snug.
What room size do I need for the Belvoir in a UK double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That allows walking space on both sides and, in most rooms, a bedside table each side too. These are our own recommendations rather than Feather & Black's, so measure your room before ordering rather than trusting the floor plan.
How much bigger is a UK king than the Belvoir double?
The UK double is 15cm narrower and 10cm shorter than the UK king, which measures 150 x 200cm against the double's 135 x 190cm. The extra length matters if anyone in the bed is tall. For the UK king we'd suggest a room of at least 2.7m x 2.9m, so check yours can take it first.
Will the Belvoir double get up a narrow staircase?
At 135 x 190cm and 28cm deep, it's a substantial mattress that doesn't fold, so tight turns in older terraces and narrow new build landings need measuring first. Feather & Black's two man delivery team carries it to your room of choice, which helps, but they can't shrink it, so check your stairwell's pinch points before you order.
Is the Belvoir UK double a good guest room mattress?
It's a sensible fit. The UK double is the size visiting couples expect, and the Belvoir's firm tension with a softer pillowtop suits a mix of guests better than anything at either extreme. The 135 x 190cm footprint also leaves room in a smaller second bedroom for a wardrobe and drawers alongside it.