TheraPur ActiGel Glacier 4000 Combination King Size 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
£1,599
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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
- More room each than a UK double: You get 75cm each, which is 7.5cm more per person than a UK double, enough to stop your arm landing on your partner every time you turn.
- Length for a tall partner: At 200cm, or 6ft 6in, the UK king is 10cm longer than a UK double, so taller sleepers can lie straight without their feet hanging off the end.
- Calmer nights on different schedules: The pocket and micro springs absorb motion, and the wider UK king surface puts a little more distance between you when one of you gets up hours earlier.
- Cooler with two bodies in the bed: Two people give off more heat than one, so the graphite-infused cover on the UK king helps if you or your partner tend to wake up warm.
- Fits rooms a UK super king won't: We suggest at least 2.7m x 2.9m for the UK king, which leaves space for wardrobes in a new build main bedroom where a UK super king would crowd the room.
This size suits you if...
You share the bed every night and keep waking each other on a UK double, one of you is tall enough that the end of the bed gets in the way, or you get up at different times and want the other person to sleep through it.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m. We'd recommend the UK double instead, which we suggest for rooms of at least 2.6m x 2.8m.
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FAQ's
Is the TheraPur ActiGel Glacier 4000 UK king big enough for two people?
Yes, for most couples. The UK king gives you 75cm each, which is 7.5cm more per person than the UK double. That extra width is what lets you turn over without nudging your partner. If one of you sprawls or a dog shares the bed, the extra space starts to feel tight, and the UK super king may suit you better.
What size bedroom do I need for a UK king TheraPur ActiGel Glacier 4000?
We suggest allowing at least 2.7m x 2.9m for a UK king. That gives you enough space to walk around the bed and open drawers. In a new build main bedroom, measure after the wardrobes are fitted, because built-in units can take more floor space than the plans suggest.
Is the UK king TheraPur ActiGel Glacier 4000 long enough for a tall person?
The UK king is 200cm long, or 6ft 6in, which is 10cm longer than the UK double. If you have a tall partner, the extra length usually matters more to them than the extra width. Sizing up to the UK super king won't help with length, because the two sizes are the same length.
Should I get the TheraPur ActiGel Glacier 4000 in a UK king or UK super king?
The UK super king is 30cm wider and gives 90cm each, so you'd have 15cm less each on the UK king. The UK super king needs at least 3m x 2.9m. If your room is smaller than that, the UK king is the better fit, and most couples find it plenty.
Will I feel my partner moving on a king size TheraPur ActiGel Glacier 4000?
Less than on a narrower bed. The pocket and micro springs absorb motion, and on a UK king you each have 75cm, so you start with more distance between you. You may still notice a little movement when someone gets in or out, but early starts should be less likely to wake the other person.