Phoenix,
Thank you for the help you’ve already given me! I have another question as I’m digging deeper into this. As you already know, I’m looking into Latex Bliss mattresses. One option on the “natural”, but apparently not on the “all-natural” models, is something they are calling “Active Fusion.” It is supposedly a “phase-changing” (?) something-or-other in the top fabric. I think they said that they infuse gel into the thread? I know this is a brand you support, but is there anything to the claims that this stuff supposedly cools down a warm sleeper and warms up a cold sleeper? I can’t tell the difference just by lying down on them in the mattress store, but will this stuff make a noticeable temperature change or is it just another marketing ploy by a mattress manufacturer?
And if you think it does work, then will putting a waterproof mattress protector on top of it negate any possible positive effect it would have?
Thanks again! 
:cheer:
Hi Erroneous,
The “Active Fusion” is a phase change material that changes its state with temperature and as it does so absorbs heat and then releases it again as necessary. It’s just a name for many products that are using similar technology in either foams or in ticking or even mattress protectors. For example Celsion talalay latex uses a phase change material in their Talalay to regulate temperature even though Talalay latex is already one of the most breathable foams.
There is a lot of emphasis these days on sleeping cool and it’s the newest marketing thrust that’s being pursued by almost every manufacturer by using blue colors everywhere and describing everything in terms of sleeping temperature. This is also one of the driving forces behind all the “buzz” around the newer gel foams which can also absorb heat if they are in the upper layers of the mattress. These materials can have some effect and in combination with other materials and “pieces” of the sleeping temperature puzzle can certainly help with regulating temperature although there are also other materials that encourage ventilation and breathability like wool and more open celled foams and various types of bedding using fabrics like linen or cotton or bamboo which will also make a big difference.
So overall it’s based in fact but if you listen to the marketing it sounds like everyone that uses even one of these materials will be sleeping on snow while in fact it’s just a piece of the puzzle and each “piece” can add another increment of effect.
A waterproof mattress protector of the “breathable membrane” type will not be as breathable as other types like stretch knit cotton or wool so while it would still have some effect … even through the protector … some of the effect could be negated by the less breathable protector. The goal is to have as much airflow around the surface of the skin as possible and to absorb moisture and then release it gradually into the air through evaporation. All the layers that are close to the skin and the amount you sink into a mattress and the materials you are sinking into will all have an effect on sleeping temperature.
So the foams used in the upper layers, the materials used in the ticking (cover) and quilting of the mattress, the materials used in a protector, the type of sheets, the type of pyjamas, and the bedding and blankets used will all be part of regulating temperature. As a rule … synthetic materials like polyester are warmer than more natural fibers as well. The goal of the manufacturer is to convince consumers that they are always too hot and always have been and that they need absolutely everything that they make to have any hope of making it through the night without burning to a crisp. Of course everyone is in a range of temperature comfort and some sleep much hotter than others. For those that need it … there’s lots of material combinations that can help but the solution isn’t usually any one of them.
Phoenix