Abstract:Solar heating system is a promising sustainable energy source for buildings. Simulation models using EnergyPlus and TRNSYS were used to optimize the solar heating building enclose thermal insulation. The sensitive analysis of active solar heating system design parameters and energy consumption was conducted to study the influence of building envelope thermal performance on the active solar heating system. The two object functions, investing cost and lift time cost, were used to optimize the building envelope insulation. The results show that not only the energy consumption can be reduced by increasing the building envelope thermal performance, but also can minimize the investing cost.