What This Means
This research suggests that noise from residential air-source heat pumps — a type of heating and cooling system that is becoming increasingly common — can affect both sleep quality and daytime wellbeing. In a controlled laboratory study, 40 healthy adults each slept three nights under different conditions: one quiet night and two nights with heat pump noise at levels representing either a tilted (slightly open) window or a fully closed window. The study found that while overall sleep duration and efficiency were not dramatically changed, the heat pump noise (especially with a tilted window) caused more brief awakenings during the night and greater feelings of sleep disturbance compared to the quiet condition. This suggests that even if people appear to sleep roughly the same total amount of time, the quality of their sleep may be quietly undermined by this type of noise.
During the daytime portion of the study, participants were asked to read texts while exposed to heat pump noise, and they reported more annoyance, difficulty concentrating, and mood disturbances compared to when they read in a quiet environment. Notably, people who experienced the noisy condition after a quiet one reported higher annoyance levels, suggesting that the contrast between quiet and noise may amplify how bothersome the sound feels.
This research suggests that heat pump noise, though often considered relatively low-level, may have real effects on residents' sleep and daily functioning, and these health impacts deserve consideration as heat pump use grows. The authors caution that because the study was done in a laboratory, the results may not perfectly reflect real-world experiences at home, and they call for larger, longer-term studies to better understand these effects.