Millbrook Wool Luxury 4000 Pocket Mattress
Mattress
Millbrook Wool Luxury 4000 Pocket Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
28
Layers
5
Layer Details
- Cover. A soft-touch cotton-viscose fabric infused with M-Pure, a 100% natural, plant-based treatment. It's naturally fire resistant, which means no added chemical fire retardants in the cover.
- Comfort fillings. Luxury Hampshire fleece wool blended with layers of English cotton, traditionally hand-tufted. Wool and cotton breathe well, so this layer helps keep you at a steadier temperature through the night.
- Mini pocket springs. Small, individually cased springs sit near the surface to add comfort and soothing pressure relief. They respond to your shape more precisely than fillings alone would.
- Pocket spring support system. 4000 pocket springs zoned in 7 areas, an arrangement Millbrook calls ErgoZone 7. Each spring is individually encased and adapts to your movement, which means support that follows your body rather than the whole bed dipping.
- Edge support. Metal rods sit above and below the spring unit, held in place with butterfly clips. This reinforces the edges, so you can use the full width of the mattress without the sides sagging.
Layer details from mattressonline.co.uk product page, September 2026.
- Real space for one: At 30cm wider than the UK single, this size lets a lone sleeper stretch out across the medium firm surface without paying for width they'll never use.
- Fits compact bedrooms: It's 15cm narrower than the UK double, which can be the difference between a door that clears the bed frame and one that doesn't.
- Full width is usable: Metal edge rods with butterfly clips firm up the sides, so on a narrower mattress like this you can sleep right at the edge without rolling off.
- Cool in a small room: Compact bedrooms and lofts warm up quickly, and the Hampshire wool and English cotton fillings breathe far better than foam would in that setting.
- Support for occasional sharing: The 4000 pocket springs respond individually, so when a couple does share for a night or two, one person's movement won't rock the other.
This size suits you if...
You sleep alone most nights and have outgrown a UK single, but your room can't take a standard double, or you're furnishing a guest room or holiday let where couples stay occasionally rather than every night. It also suits a teenager ready for more width in a bedroom that still needs floor space for a desk.
Consider another size if...
You share the bed every night and want proper space each. We'd recommend the UK double instead, which gives 67.5cm each for two sharing; allow at least 2.6m x 2.8m of room for it.
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Is a small double Millbrook Wool Luxury 4000 big enough for two adults?
For occasional nights, yes. Across the 120cm width, the 4000 individually cased pocket springs limit how much you'll feel a partner move. For nightly sharing it will feel snug, and the UK double, 15cm wider, is the better long-term choice. As a guest room mattress for visiting couples, the small double is a sensible pick.
What room size do I need for a small double mattress?
We suggest at least 2.4m x 2.8m for a UK small double. That leaves room to walk around the bed and open drawers, which matters here because this is a heavy, hand-tufted mattress with turning handles: you'll want space to rotate it. In a box room or loft, measure the door swing before ordering.
How does the small double compare with the double in this mattress?
The UK small double is 15cm narrower than the UK double, and both are the same length at 190cm. The construction is identical: same 4000 springs, same wool and cotton fillings, same medium firm feel. The choice comes down to who's sleeping on it and how much floor your room can spare.
Is this size a good choice for a teenager's room?
Often, yes. A teenager who's outgrown a UK single gets 30cm of extra width, and the medium firm, zoned support suits back and front sleepers as they grow. The small double leaves more floor free than a full double, so a desk or wardrobe still fits. It is firm, though, so try similar feels first if they prefer soft.
Where can I buy the Millbrook Wool Luxury 4000 in a small double?
Compare the retailers listed on this page; the prices shown are updated as retailers change them. Stock in 4ft sizes can move around, so if availability looks thin, check back rather than assuming it's gone. Bedding is easy: standard small double fitted sheets and a regular double duvet fit this size.