Creating favorable climatic conditions for plant cultivation in growing facilities is directly linked to the stable operation of the heating system, especially during the winter months. Consequently, predicting the thermal regime of a space in the event of an emergency heating system shutdown is an extremely important task for the agricultural sector. Research object: cultivation facilities designed for year-round plant growth. Research subject: patterns of internal air temperature changes (both dimensional and dimensionless) during an emergency heating system shutdown. Research objective: to predict the thermal regime of the cultivation facility following an emergency shutdown of the heating system. Research methods: theory of regular thermal regimes, according to which the temperature field at all points of the cooled body (in this case, the heating system) changes uniformly, following an exponential law; computer-based software calculations. Research results: the internal air temperature in the industrial greenhouse will reach its critical value of 8 ℃ approximately 1 hour and 15 minutes after the heating system is turned off. The duration of the internal air temperature decrease from its initial value to the conditionally critical value of 8 ℃ is minimally affected by the total thermal losses and, on average, increases by approximately 0.2 hours for every 0.1 m²⋅K/W of the thermal resistance of the enclosure. Thus, the cultivation facility, as a construction object with relatively low levels of thermal protection, should be equipped with a heating system that meets higher reliability standards.