I am working on a new project which consists in 5 buildings, all have its own HVAC system designed, 3 of them have a complete HVAC, and the other 2 will only have Mechanical Ventilation to cool the building (project in central Mexico no heating needed). My approach is to model each building independently and then add up the results. My question is if for the 2 buildings that only have Mechanical Ventilation I should also include cooling and heating, according to appendix G I should if they were individual buildings. Any advice would be grateful.