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We've dedicated hundreds of hours to testing mattresses and sleep accessories, and rely on a team of testers of differing weights, temperature preferences, and sleeping positions to evaluate each product.
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Hypnia mattress topper composition
The Hypnia Ultimate mattress topper is one of the thickest mattress toppers currently available in the UK.
It comprises of:
- 8 cm (3.14”) memory foam
- Machine-washable polyester cover
- Anti-slip base
The memory foam provides a soft, body-hugging feel that contours around the joints. 💪
See how this works below:
You can see how the foam adapts to the shape of the body before returning to its original form.
This makes it a perfect choice for those looking for a mattress topper to soften the feel of their mattress or relieve pressure on the joints.
We’ll go into more detail about the comfort of the Hypnia topper further down. ⏬
Hypnia topper cover
The Hypnia mattress topper is encased in a removable cover made from 100% polyester. 🧵
The cover is OEKO-Tex certified, meaning it's been tested against harmful chemicals.
While polyester may not be as breathable as cotton, it’s highly durable and flexible, making it easy to remove from the topper.
We had no issues when removing the cover from our Hypnia topper.
It also features an anti-slip base, which helps to keep the topper secure on the bed.
We found this particularly useful since we have an ottoman bed frame and often need to lift up the base of the bed.
However, since the topper doesn’t have straps, we found that the Hypnia topper sometimes moved around at night. 🙁
We’ll go into more detail about this in our section on the drawbacks.
Can you wash the Hypnia mattress topper cover?
The Hypnia mattress topper cover is machine-washable.
Simply pop the cover into your machine at 40°C with your regular laundry detergent. 🧼
Does the Hypnia mattress topper sleep hot?
Memory foam is known for creating a slightly warmer sleep, so we were apprehensive to try this memory foam topper during the peak of summertime. ☀️
During testing, we experienced a slightly warmer sleep with the addition of the Hypnia mattress topper. 🌡️
We wanted to test this further with our thermal camera to see how well the Hypnia topper dissipated heat.
We lay on the topper for 10 minutes, analysed how well the heat dissipated after 5 and 10 minutes, and compared this with the Simba Hybrid mattress.
Take a look at the results:
|Temperature results immediately after laying||Temperature results 5 minutes after laying||Temperature results 10 minutes after laying|
|Simba Hybrid with Hypnia topper||31.1°C||27.6°C||26.1°C|
|Simba Hybrid without Hypnia topper||29.1°C||27.3°C||26.5°C|
As you can see, the temperature is slightly warmer immediately after laying on the topper than with the Simba Hybrid.
But the Hypnia topper dissipated heat slightly faster than the Simba Hybrid. ♨️
Our results and experience concluded that you might experience a slightly warmer sleep with the addition of the Hypnia topper.
However, it shouldn’t make too much of a noticeable difference to your overall sleeping temperature.
Hypnia mattress topper sizes
The Hypnia mattress topper is available in standard UK mattress sizes, so it should sit flush with your mattress.
These sizes include:
- Hypnia mattress topper single size: 90 x 190 cm (3’ x 6’3”)
- Hypnia mattress topper small double size: 120 x 190 cm (4’ x 6’3”)
- Hypnia mattress topper double size: 135 x 190 cm (4’6” x 6’3”)
- Hypnia mattress topper king size: 150 x 200 cm (5’ x 6’6”)
- Hypnia mattress topper super-king size: 180 x 200 cm (6’ x 6’6”)
The Hypnia Ultimate mattress topper is 8 cm (3.14”) deep, which is fairly thicker than the 5 - 7 cm (1.9 - 2.7”) standard mattress topper depth.
However, ours fell slightly shorter than this at just over 7 cm (2.7”).
Unfortunately, the Hypnia mattress topper has no warranty, so it wouldn't be possible to request a replacement for this slight anomaly.
Hypnia mattress topper delivery
The Hypnia Ultimate topper is delivered for free within 2 - 3 working days.
Our Hypnia topper arrived quickly in a large rectangular cardboard box. 📦
We were surprised by the size of the box, which was just a little bit smaller than a box you’d typically receive mattresses in.
This made it a little inconvenient to store, so keep this in mind if placing your order before you are ready to unbox your topper. 🕓
The Hypnia topper is also challenging to store away once unboxed.
We recommend the Fine Bedding Company Dual Layer topper if you’re looking for a topper that will only be used occasionally.
This topper can be separated into two parts and folded away into the reusable storage bag it comes with.
Unboxing the Hypnia mattress topper
To unbox your Hypnia Ultimate mattress topper, you first need to remove it from the cardboard box.
It’s quite heavy, so we recommend doing this with another person to make things easier. 👯
You can then carefully cut away the plastic layer and watch your Hypnia topper expand like magic.
Once all the plastic has been removed, your Hypnia topper should expand fully.
However, some toppers may take longer, so we recommend waiting an hour or two before laying down on it.
You should put your mattress protector and sheets over your mattress topper and mattress.
You may need to purchase extra deep sheets and protectors if your mattress is already fairly deep.
Does the Hypnia topper smell?
The Hypnia topper had an unusual smell when first unboxed. 👃
This is known as off-gassing and commonly occurs in vacuum-sealed products to release trapped odours.
Off-gassing isn’t harmful, and the smell should disappear after a few hours.
By the time we were ready to use the Hypnia mattress topper in the evening, the smell had disappeared.
Should you buy the Hypnia mattress topper?
The Hypnia mattress topper is an excellent choice for those with a firm mattress looking to soften the feel of their sleep. ☁️
If you wake up with aches and pains on your current mattress, the Hypnia topper can help relieve pressure on these areas.
The Hypnia mattress topper encourages correct spinal alignment and support in the lumbar region, particularly for side sleepers who need more sinkage.
However, if you already have a soft mattress made with memory foam, there may be other options than the Hypnia topper. 🤔
Instead, consider a firm mattress topper or replacing your mattress altogether.
Our guide on the best mattresses in the UK has some excellent options.