TheraPur ActiGel Glacier 4000 Combination Small Double Mattress
The TheraPur ActiGel Glacier 4000 Combination Mattress pairs a graphite-infused cooling cover with zoned ActiGel foam and pocket springs, which means you get pressure relief with less trapped heat.
- Graphite-infused cover keeps you cooler
- Zoned foam eases pressure
- Springs absorb motion
£1,439
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TheraPur ActiGel Glacier 4000 Combination Mattress
More available sizes
Mattress details
Mattress
TheraPur ActiGel Glacier 4000 Combination Mattress
Size
Firmness
Medium
Construction
Foam
Gel
Pocket Spring
Depth (cm)
28
Layers
3
Layer Details
ActiCool+ cover
A graphite-infused cover that TheraPur describes as its coolest ever. It's the surface you lie on, so it's there to keep you feeling cooler through the night.
ActiGel foam
4cm of zoned ActiGel foam that relieves pressure without trapping heat. You get cushioning where your body needs it, without the warmth that foam can hold.
Pocket and micro springs
Responsive pocket and micro springs that absorb motion. They give the mattress its support and should limit how much you feel a partner moving.
Layer details from dreams.ie product page, November 2026.
Key benefits
- Room to spread out on your own: At 30cm wider than the UK single, you can turn over or sleep with an arm flung out without finding the edge.
- Fits rooms a UK double would crowd: It's 15cm narrower than the UK double, which can decide whether a box room door opens fully or catches the side of the bed.
- A cooler surface for a small, warm room: Compact bedrooms heat up quickly, so the graphite-infused cover, designed to keep you cooler, helps if you tend to wake up warm.
- Copes with the occasional couple: The pocket and micro springs absorb motion, so when guests share for a night or two, one turning over is less likely to disturb the other.
- Bedding is easy to buy: 4ft is a standard UK size, so small double fitted sheets turn up in most shops, and a standard double duvet sits comfortably on top.
This size suits you if...
You sleep alone but like plenty of room to stretch, or you're furnishing a small guest room where couples only stay a night or two.
Consider another size if...
You share a bed with a partner every night. We'd recommend the UK double instead, which gives 67.5cm each for two sharing; we suggest at least 2.6m x 2.8m for it.
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FAQ's
What room size do I need for a TheraPur ActiGel Glacier 4000 UK small double?
We suggest at least 2.4m x 2.8m. That's our own guidance, and it leaves space to walk round the bed and open drawers. In a box room, measure where the door swings to before anything else, then compare the retailers listed on this page.
Can two adults sleep on the TheraPur ActiGel Glacier 4000 small double?
For a weekend, yes. The pocket and micro springs absorb motion, so a restless guest is less likely to wake the other. Every night is a squeeze, though. The UK double gives 67.5cm each for two sharing, and we suggest at least 2.6m x 2.8m for it.
Is the TheraPur ActiGel Glacier 4000 small double long enough if I'm tall?
The UK small double is 190cm long (6ft 3in), the same length as the UK single and UK double. If your feet already reach the end of your current bed, the UK king is 10cm longer, but it needs more room: we suggest at least 2.7m x 2.9m.
Is a UK small double a good upgrade from a single for a teenager?
Often, yes. The UK small double is 30cm wider than the UK single at the same length, so a growing teenager gains turning room. The trade-off is floor space: allow at least 2.4m x 2.8m, against our suggested 2.1m x 2.8m for the UK single.
What sheets and duvet fit a TheraPur ActiGel Glacier 4000 small double?
Buy small double (4ft) fitted sheets made for 120 x 190cm. A standard double duvet works on top and hangs over the sides a little. The mattress is 28cm deep, so check the sheet's pocket depth, as shallow ones can pop off the corners.