Hi Dennis --

Thanks for your question. This is really the flip side of all the "sleep cooler" marketing that mattress companies do these days, isn't it?! The reality is that the way they should be describing most of the features that have been added to mattresses in recent years is "sleep not hot" -- but of course that doesn't sound quite as compelling. :)

The bottom line is that unless you are using an add-on solution (sold separately from the mattress) that is specifically designed to pump cool air or water closer to your body, you probably aren't in much danger of sleeping "too cold" on account of anything going on with your mattress.

In most cases, the cooling features of a mattress are designed to keep the mattress feeling cooler for a limited period of time (e.g., 15-30 min), which is hopefully enough time for the person to fall asleep, after which they have limited capacity for additional cooling. As such, having a mattress like this in a cold space like yours will likely feel a bit cooler when you first get into it than that same mattress would in a warmer space. It should also feel a bit cooler to get into than a traditional mattress in your same space. But all of these differences will gradually fade as the mattress reacts to the warmth of your body.

Going a step further, in the case of gel, phase change material, or other cooling elements added to memory foam, these are generally designed more to counter-balance the warming aspects that are somewhat inherent to sleeping on memory foam (high-density foam with deep cushioning that contours closely to your body). As such, with rare exceptions, these features will make the mattress feel cooler than sleeping on an ordinary memory foam mattress, but generally not cooler than sleeping on a mattress with no memory foam at all.

I hope that helps!