Where there are smart systems such as BMS in place, modelling must consider normal operating conditions, with the heating and cooling system in operation regardless of the control strategy.
In order for the design team to size the heating/cooling plant, they will carry out modelling to calculate the heat/cold loss throughout the year. Results of these calculations must be submitted, with the heating/cooling plant specification which would demonstrate that the building has been designed to ensure internal winter/summer temperatures will not drop below an acceptable level, and that in effect the winter TOR is zero.
14 Apr 2023 Applicability to UK NC2018 and UK/Int V6 confirmed