Distribution of heat gain and direction for energy efficiency of residential buildings in hot summer and cold winter area

Analyses and calculates the hourly heat transfer through each building envelope and the proportion of it to the total heat gain for the four rooms with the response factor method for multi-layer wall thermodynamic system under a typical weather condition in Nanjing. The results show that in the typical summer weather condition, the influence of unit area building envelope on the room heat gain is, in a descending order, radiant heat gain through the window, heat transfer through the window, heat transfer through the roof, heat transfer through the west/east wall, heat transfer through the south wall; the heat gain from solar radiation is always the main portion in daytime; the hourly heat gain through west windows caused by radiation and transfer increases significantly with the increase of the west window-wall area ratio; in this area, it is suggested to improve the performance of the window shading, to reduce the heat transfer coefficient of the window, to properly control the area of the south window, and to strictly control the window-wall area ratio of the west/east wall, and the west window-wall area ratio should not be greater than 0.2.