To limit the probability that random/arbitrary hours of operation of the ventilation system in the reference house will be used as input in the energy model calculations, which could lead to inaccuracy of the model, which could lead to overestimation of the energy used by the reference building or underestimation of the energy used by the proposed building, which could lead to excessive use of energy, which could lead to an unacceptable effect on the environment.
To limit the probability that the energy model calculation method will not appropriately account for the ventilation of the reference house, which could lead to occupant-dependent factors being treated inconsistently in the calculations, which could lead to inaccuracy of the model, which could lead to overestimation of the energy used by the reference building or underestimation of the energy used by the proposed building, which could lead to excessive use of energy, which could lead to an unacceptable effect on the environment.