Dreams TheraPur ActiGel Glacier 3800 Combination mattress review: Ideal for hot sleepers

The Dreams TheraPur ActiGel 3800 Combination mattress sits in the middle of the brand’s TheraPur range, offering exceptional cooling to hot sleepers. In fact, I think it’s one of the best mattresses I’ve tested when it comes to temperature regulation. The brand’s “ActiGel” and “PurFibre” foam layers have perhaps played a part in this, as have its well-spaced coils for airflow (more on all that later).

As well as sleeping on the mattress myself, I asked several very hot sleepers to try it out and all of them reported back on how cool they had found the bed throughout the night. It’s also comfortable, particularly for back sleepers and side sleepers, with a good combination of comfort and support on offer. But let’s delve under the covers to look at the mattress in more detail.

Dreams TheraPur ActiGel Glacier 3800 Combination mattress review: What you need to know

The Dreams TheraPur is a hybrid mattress, made up of a combination of springs and foam. However, unlike many of the bed-in-a-box mattresses we’ve reviewed, the Dreams TheraPur is made to order and comes delivered flat, wrapped in a large plastic bag. Speaking of delivery, Dreams’ delivery team will either deliver the mattress to your door or, for an extra £29, a two-man team will bring the mattress to a room of your choosing. Considering that even the single mattress weighs 30kg, I’d recommend taking advantage of this. You can select your delivery date and time from Monday to Saturday.

Upon opening the plastic packaging, there was a very strong off-gassing smell. This was my only major bugbear with the Dreams mattress – while these chemicals are harmless, the smell lingered for four days and was, on the first day, strong enough to give me a headache even with the room being ventilated.

The Dreams TheraPur is an imposing mattress at 28cm high: the same height as our favourite hybrid mattress: the Simba Hybrid Pro. Unlike the Simba, however, much of the height is down to the large pillow top attached to the mattress. The mattress has a cooling quilted cover that does actually feel cool to the touch. Underneath this is a “PurFibre” comfort layer and 20mm of “ActiGel” foam: the former is designed to help your mattress bounce back to its original shape after use, while the ActiGel features gel-infused foam and an open-cell structure to allow heat to dissipate quickly. Underneath this, another 20mm layer of ActiGel zoned foam makes up the rest of the pillow top.

A PurFibre support layer sits on top of a layer of comfort springs, followed by a base layer of traditional pocket springs. The number of coils varies according to mattress size: for instance, a king has 3,741 springs in total. Edge support is also aided by a “fully encapsulated” side support.

As you would expect from a pillow top mattress, you can’t flip the Dreams TheraPur, but you should rotate it regularly. The double size I tested weighed 45kg, making the handles on the side of the mattress a very welcome addition, but I’d suggest that this is still ideally a two-person job. You’ll also get a 100-night sleep trial, with the option to exchange the mattress if it doesn’t suit, along with a 10-year guarantee.

Dreams TheraPur ActiGel Glacier 3800 Combination mattress review: Price and competition

There’s no getting away from the fact that the Dreams TheraPur is an expensive mattress. Prices start at £1,299, rising to £1,699 for both the small double and double sizes. A king size is £1,899 and a super king comes in at £1,999. There are also two EU sizes – an EU small single at £1,299 and an EU single at £1,399.

Compared to other “cooling” mattresses, the Dreams TheraPur comes in high on the price scale. The Emma NextGen Cooling mattress (now renamed the Emma Hybrid Thermosync mattress) costs £918 for a king size, and the Simba Hybrid Pro retails at £1,249 for a king.

Another mattress that I found sleeps cool is the Panda Hybrid Bamboo Pro mattress, which comes in at £1,390 for a king size. Again though, this is considerably cheaper than the Dreams TheraPur. It’s worth noting that these mattresses arrive rolled and vacuum packed in a box, while more traditional ‘flat’ mattresses, such as the Dreams Therapur, often command a higher price tag. My advice would be to look out for a sale at Dreams and pick up the mattress for a lower price. If it’s simply too expensive, you could also consider another mattress from the TheraPur range with fewer springs.

Dreams TheraPur ActiGel Glacier 3800 Combination mattress review: Comfort and performance

If you’re a hot sleeper, this may well be the mattress for you. Personally, I found it rather chilly, though I should admit that I tested the mattress during winter. I also run cold and I’m well aware that many people tend to get a little clammy or even overheat in bed. Whether or not it’s thanks to the ‘cooling Actigel foam’, the Dreams TheraPur mattress feels cool to the touch. Of course, the mattress is going to warm up a little as you lie on it, but my husband (traditionally a hot sleeper) felt cool and comfortable on it all night.

To verify the Therapur’s cool credentials, I conducted some tests. I heated up an area of the mattress surface with a heat pad, weighing it down with a paperback book and a 2.5kg weight. The pad was initially heated to 75°C and was removed after it reached 50°C. After one minute the temperature dropped to 30°C, cooling down to 21°C after 10 minutes. This was an extremely effective dispersion of heat: even more so than the Emma NextGen Cooling mattress, which dropped to 22°C after 10 minutes.

I also tested whether the mattress could effectively regulate body temperature by sitting on the mattress with the thermocouple underneath me. Once the thermocouple reached 30°C, I got off the mattress and weighed the thermocouple down again with the book and 2.5kg weight. Impressively, the temperature dropped to 20.4°C after 10 minutes.

Dreams describes the TheraPur mattress as medium firm, but I’d suggest it’s a little firmer than this. The pillow top does give a lot of initial softness, which is fantastic for cushioning and a little contouring around pressure points. But the sprung foundation makes for an extremely firm feel. However, testing for sinkage did show that, with a pile of 2.5kg weights (totalling 10kg) in the middle, the mattress’ surface did dip by 35mm. This is slightly more than the sinkage on the Emma NextGen Premium mattress, for example. However, the mattress didn’t dip any further at the edge, where sinkage was also 35mm. This is particularly impressive for a pillow top mattress, which often doesn’t have great edge support. The Dreams TheraPur allows you to spread out and use the entire surface of the mattress, while also providing a stable structure to sit on.

I was impressed by the build quality of the Dreams TheraPur, with the mattress being well-made and neatly stitched together. Obviously we can’t judge durability over a short testing period, but it’s worth noting that pillow top mattresses often have a slightly shorter lifespan than their counterparts. This is because the pillow top section will wear down before the core and, because you can’t flip the mattress, all wear will be concentrated on one side. So, in the case of the Therapur, the foams in the pillow top are likely to wear down quicker.

Sleep position wise, I’d recommend this mattress primarily to side and back sleepers. There’s plenty of cushioning from the pillow top to prevent side sleepers from experiencing pressure build up at their shoulders and hips. But the firmer coils underneath should also do a great job of supporting the lumbar region for back sleepers, allowing the spine to remain aligned. Front sleepers however are likely to find the mattress too soft because of its pillow top and could end up with their hips sinking too far into the mattress.

Dreams TheraPur ActiGel Glacier 3800 Combination mattress review: Verdict

The Dreams TheraPur mattress is a wise investment for hot sleepers, doing an excellent job of keeping them cool throughout the night. At 28cm deep, it’s quite a hefty mattress and certainly looks like a premium buy, which is no bad thing considering its hefty price tag.

Price aside, this mattress does an outstanding job of keeping you cool and, if overheating is something you usually struggle with at night, I think it’s worth the investment. My heat tests showed how impressive its temperature regulation is, and I’d argue it’s definitely one of the best cooling mattresses you can buy.

If you’re not a hot sleeper though, it’s not as easy to recommend – I found it far too chilly to get comfortable as someone who runs cool.

Nevertheless, the pillow top adds a layer of sumptuous comfort that will appeal to many sleepers, while the springs provide plenty of support. As noted above, pillow top mattresses have a slightly shorter lifespan in general. A 100-night sleep trial will give you time to decide if the mattress is for you, but do be aware that you can only exchange it for another product – refunds aren’t offered.