The screed above an underfloor heating system acts like a thermal store. It is normal for the initial heat-up time to take about one hour longer than a room having a radiator but conversely the room will remain warm for a longer period after the system has been switched off.

Many underfloor heating systems are controlled by a set-back thermostat, which does not simply switch the system off at night but uses a lower setting (i.e. 15ºC). This facility would improve the response time, and is recommended for new dwellings.