Building energy simulation is essential for most architectural design projects. Many models have been developed to predict the indoor air temperature and relative humidity as well as the building’s heating and cooling loads. However, in most building energy analysis the calculation of heat conduction through walls usually neglects the transport and storage of moisture in porous building materials, and the interaction between hygrothermal transfer and airflow inside the building. An accurate heat load (both sensible and latent load) determination requires a calculation of the coupled heat and moisture transfer in building envelopes and the hygrothermal interactions between the envelope and the environment. This paper evaluates the accuracy and the applicability of three thermal models in EnergyPlus (CTF—Conduction Transfer Function model, HAMT—Combined Heat and Moisture Transfer model, EMPD—Effective Moisture Penetration Depth model) for calculating moisture effects on building energy consumption in different climate conditions. The simulation results are compared with field measurements. The effects of different room infiltration rate on the accuracy of different models are also analyzed.

The opening of building facade has a strong influence on energy consumption. However, making full use of solar energy and natural wind to reduce energy consumption is a challenge for architects. The aim of this study is to investigate the influence of the facade design on energy consumption from an operable aspect. The evaluation comes from an integrated approach combining daylighting, thermal performance and natural ventilation. The study is based on computer simulation technique utilizing simulation tools EnergyPlus and Fluent. To facilitate the use of EnergyPlus, a simple graphic user interface has been developed by Matlab. The interface can set the parameters of EnergyPlus and process the wind pressure coefficients calculated by Fluent. With this interface, three type facade configurations with different areas or position changes have been modelled. The results show that opening area, compared with opening positions, exerts a greater influence on energy consumption. The opening position changes have a positive influence; however, this influence is small: at around 2%.