Hi Nia,

Many thanks for your question about Simba mattresses and its nice to hear back from a previous customer.

We're sorry to hear you're having such issues with your sons Simba mattress. It's all too common for us to hear of people having the same problem with their Simba bed being too hot for them to sleep properly in. We can provide some guidance as to fixing the issue but the real answer is you're never going to be able to properly remove the heat from this mattress.

Why is my Simba mattress so hot?
The Simba mattress is a synthetic mattress that's primarily made up of different types of Simba proprietary memory foam. It's listed as a cooling foam they have created called 'Simbatex'. They give the following information on their mattress website.

"Simbatex is our specially developed cooling foam. It has an open-cell structure which keeps you cool by encouraging air flow through the mattress, and uses graphite particles to filter heat away. So you enjoy the cloud-like comfort of foam, without it getting too hot and sinky."

Image from: Simbasleep.com

They're right that most foams have an open cell structure however, with all these viscoelastic foams, they require heat to be able to mould to the sleeper. This is the fundamental flaw with all memory foams as it means they require heat to work effectively. No amount of tweaks or other materials is going to fundamentally change this property. The only way to remove it is to change the foam to a more breathable material, like cotton or horsehair.

Simbasleep are trying to reduce this by using graphite to reduce the heat but in our experience of many different hybrid foams they are still far warmer than natural fibres or more breathable pocket sprung mattresses.

What doesn't help is the fact there's zero detail on the foam such as the depth, density or technical specs of this memory foam equivalent. So it's really hard for us to be able to advise on what fibres would work best to reduce the heat. If you look at the cutaway above their no real detail on any of the 5 or 7 Simba mattress layers.

Probably no fibre will help remove the heat built up, which is supported by the fact that you've tried a feather (which are super breathable) but it doesn't remove the heat issue with the Simba mattress.

What springs does the Simba mattress use?

It's also worthwhile mentioning the pocket spring unit the Simba mattress uses. The Simbasleep mattress also uses micro springs which is how they get their 2500 or 5000.

"The Hybrid has five layers and up to 2,500 springs, and the Pro has seven layers and up to 5,000 springs."

Above is an example of some micro springs. Note how small they are and the fact they are covered in synthetic spunbond polyester compared to larger pocket springs.

Again there is no detail on the pocket spring gauge or tension of these springs. We don't use micro or HD springs. You can find out exactly why in the video below, but we find that standard pocket springs are far better for support. With micro springs providing zero support or use in a mattress other than inflating the spring count.

Will a topper cool down my memory foam bed?

Mattress toppers can help soften a bed that's too firm and also help provide a barrier against the mattress for things like perspiration and sweat. As you've experienced there's only so much a topper can achieve and heat reduction is not something a mattress topper can achieve with any significance. We wouldn't advise adding a latex mattress topper as this will only compound the heat. Latex is more breathable than synthetic memory and hybrid mattress foams but adding this to the mix would be an expensive mistake.

Alternatives to the Simba mattress

You would be better off swapping the Simba mattress for a full pocket sprung upholstered mattress without any memory foam. This is the best way to avoid the heat issues you've experienced. Take a look at our Origins Pocket 1500 mattress. It's also two-sided, unlike the Simba mattress which will help extend its life span significantly and help reduce mattress settlement. It features a wool top mattress comfort layer which will help keep your son far cooler than heat retentive memory foams.

Origins Pocket 1500 Mattress

1: 300GSM WOOL

2: 750GSM VERY SOFT POLYESTER

3: 500GSM POLYESTER PAD

4: ONE INCH FOAM INSULATOR LAYER

5: 1500 SPUN BOND POCKET SPRINGS

TOTAL: 1550GSM

DEPTH: 30-33CM

If you need more help Nai then please give us a call on 0161 437 4419 or info@localhost

Sleep Well

John & Ryan