OK, that might not be a huge revelation, but a new study published in Science and Technology for the Built Environment says we should pay more attention to both. According to a recent ASHRAE article on the study, the researchers selected average people in their own homes and monitored temperature, indoor air quality via CO2, and sleep quality using wearable sleep-trackers. The study found that temperature in the room is not as important as temperature inside the microclimate under the covers. The room temperature, of course, affects the temperature the sleeper experiences, but what can be described as a comfortable room during waking hours might be different for sleepers – especially those that like to sleep under heavy covers.
The other conclusion is that perception of sleep quality was related to air quality in the room. Bedrooms are often closed off from other parts of the house. Cooling loads are reduced at night because of lower shell loads and activity in the space, so the system does not run as often to circulate air. With limited forced ventilation in homes, CO2 and other contaminants can build up overnight in the bedroom. Upon waking, the sleeper experiences the poor air quality, which impacts their perceptions. This study suggests we need to consider sleep as an activity with its own temperature and ventilation requirements, like we do other waking activities. – Steve Terry, DTC HVAC & Refrigeration Instructor
