Polyvinylchloride (PVC) panel is one of the most favorite decorative materials that has been popularly applied as finishing of ceiling in residential buildings. It is about five years that the people incline to redecorate the ceiling of old buildings with PVC panel in big cities of Iran, such as Mashad. In this study, the influence of ceiling PVC panel on the cooling and heating loads of studied apartment were determined by software DeST-h. In addition, the summer natural ventilation of the mentioned apartment is investigated by determining the wind speed into the apartment through the computational fluid dynamics (CFD) software. The evaluation of environment indoor wind velocity showed that most of the apartment space is a comfortable zone. The results of studied building analyses demonstrated that using PVC panel on the ceiling can decline the energy consumption of the penthouse (fifth level) of the investigated building, which is about 3.7% and 7% for studied methods of without and with air layer, respectively. In addition, although the existence of air layer can decline the cooling and heating loads, the increase in air layer thickness did not show significant decrease on building energy consumption. However, the PVC panel is expensive and is not suitable to be used for ceiling thermal insulation, but adding a thin layer of air between ceiling and PVC panel can be a good step toward sustainable building, when the people are inclined to utilize it as a decorative ceiling.