You might consider a natural latex foam mattress instead. It doesn't have the issue of getting hard in very cold weather.Thank you I do stay warm once I am under the covers. But I learned that there is some really bad info floating around regarding memory foam, lol. That stuff is horrid. And it's not just because it turns into concrete when cold. When warm it is like quick sand. It is hard to scoot across the bed on that stuff. Even harder to get out of bed. Last night i had to put a blanket and an afghan under the sheets, because the foam was so cold.