Gel, phase-change, ventilation and fibre choice are four different mechanisms with four different lifespans. Only two of them last past the first hour.
Overheating at night usually is not the room temperature. It is a mattress holding heat, bedding that traps it, and a body clock doing exactly what it is supposed to.
Solid memory foam is the biggest cause of overheating in a modern bed. What genuinely cools a mattress, what is marketing, and the five things to fix before you spend anything.
Sleeping Express compares mattresses, beds and sleep accessories from retailers we have a verified commercial relationship with. We rank on construction, trial length and returns policy, never on commission rate.