Maintaining favorable microclimatic conditions in a residential dwelling is directly related to the stable operation of the heating system. An emergency shutdown of the heating system, especially in the winter season, can lead to serious negative consequences: disruption of thermal comfort for people in the residential building, rupture of pipelines and heating devices, flooding of adjacent premises, etc. Thus, the issue of predicting the thermal regime of a residential dwelling after the termination of heat supply is of practical relevance. The object of study: Residential premises in buildings. Subject of study: Patterns of change in the temperature of the indoor air (in dimensional and dimensionless forms), the rate of temperature drop, and the loss of thermal energy during an emergency shutdown of the heating system. Objective of the study: To forecast the thermal regime of a room in a residential building after an emergency shutdown of the heating system. Research methods: Classical theory of thermal stability of building enclosures; theory of regular thermal regime, according to which the temperature field at all points of the cooled body (in this case, the heating system) changes in the same way, obeying the exponential law; software computer calculations. Research results: In a room of a residential building, the indoor air temperature will reach the dew point (12.5 ℃) within 8 hours 42 minutes after an emergency shutdown of the heating system and zero value - after 23 hours 42 minutes. Based on the conducted scientific research, it can be stated that the thermal storage capacity of external enclosures, due to their design features, plays a primary role in preserving the thermal regime of a residential dwelling after the heating system is turned off.