Wentworth Mercer Deluxe Wool 4000 Pocket Double Mattress
The Wentworth Mercer Deluxe Wool 4000 Pocket Mattress is a firm pocket spring mattress with wool and soft synthetic fillings beneath a viscose cover.
- Suits back & front sleepers
- Wool helps regulate temperature
- Minimises partner disturbance
£849
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Wentworth Mercer Deluxe Wool 4000 Pocket Mattress
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Mattress details
Mattress
Wentworth Mercer Deluxe Wool 4000 Pocket Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Wool
Depth (cm)
29
Layers
4
Layer Details
Cover
A viscose cover, a soft breathable fabric, finished to a high standard. It gives the sleeping surface a smooth, cosy feel.
Wool
A plush layer of wool fibres for a luxuriously cosy feel. Wool also naturally helps with temperature regulation, so it tends to suit warmer sleepers.
Soft White Fibres
Soft synthetic polyester fillings layered on top of the springs for extra comfort. These add a gentle cushioning between you and the firm support below.
Pocket Springs
The core is 4,000 pocket springs, made from twice tempered steel, that adapt to your shape and movements. Each spring moves independently, which means personalised support and less motion transfer across the bed.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Space for two, in a sensible footprint: You each get 67.5cm of width, which suits most couples who sleep fairly still, although it is a little snugger than the UK king.
- Room for furniture as well as the bed: We suggest at least 2.6m x 2.8m, which in many UK master bedrooms leaves space for a wardrobe, a chest of drawers and a clear path around the bed.
- Less disturbance from a partner close by: The 4,000 pocket springs move independently, which means that when your partner turns over a short distance away, you should feel far less of it.
- Wool helps when two bodies share the heat: A shared bed warms up quickly, and the wool layer helps regulate temperature, so a warm-running couple should find it cooler than a foam-topped double.
- Simple to dress: Double sheets and a 200 x 200cm duvet are easy to find in almost any shop, so you won't need to hunt for specialist bedding.
This size suits you if...
You share the bed every night with a partner in a typical UK bedroom and want two people's worth of space without the bed swallowing the room, or you're furnishing a guest room for visiting couples who like a firmer, more traditional feel.
Consider another size if...
You or your partner are tall, sleep restlessly or like to spread out, and 67.5cm each would feel cramped. We'd recommend the UK king instead, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
What are the dimensions of the Wentworth Mercer Deluxe Wool 4000 UK double in feet?
The UK double measures 4ft 6in x 6ft 3in, or 135 x 190cm. The mattress is 29cm deep, so it sits quite high on a bed frame. If you already have fitted sheets, check that their pockets are deep enough before you order.
Will a UK double Deluxe Wool 4000 fit in my bedroom with bedside tables on both sides?
We suggest a room of at least 2.6m x 2.8m, with around 3m x 3m being more comfortable if you want a bedside table either side and room to walk round. If your room is tighter, the UK small double is 15cm narrower, and we suggest at least 2.4m x 2.8m for it.
Will I feel my partner moving on the Deluxe Wool 4000 in a UK double?
You're closer together on a UK double than on a king, so motion isolation matters more here. The 4,000 pocket springs each move on their own, which should keep most of your partner's movement on their side. Across the bed, a firm spring unit like this tends to feel steadier than a single sprung core.
Is the UK double Deluxe Wool 4000 long enough for tall sleepers?
The UK double is 190cm long, the same as the single and small double. If either of you is tall enough for your feet to reach the end, the UK king is 10cm longer and also 15cm wider. We suggest at least 2.7m x 2.9m for the UK king.
Is the Deluxe Wool 4000 UK double a good choice for a guest room?
For a guest room that couples use, the UK double makes sense: it sleeps two comfortably and fits spare rooms where a king would be too big. The firm feel suits most back and front sleepers. Lighter guests who sleep on their side may find it a little unforgiving on the hips and shoulders, though.