Application of improved grey relational projection method to evaluate sustainable building envelope performance

Buildings are energy gluttons. Improving thermal performance of building envelopes will reduce energy consumption in buildings. The development of advanced building envelope systems reducing energy losses is a critical research frontier. This study introduces a simple but reliable methodology for building envelope evaluation and optimization in the conceptual stage. An improved grey relational projection method is proposed to select the optimum building envelope alternative. A combination weighting method combining the subjective weighting method and the objective weighting method is adopted to calculate the weights of the factors and sub-factors. The relative projection values of the alternatives are calculated. And the optimum alternative is obtained. An example is given to demonstrate the proposed method. Finally the proposed method is verified. The results show that this method is simple and practical, and it has potential as a powerful tool in building envelope evaluation and optimization for building owners, manufacturers, designers, and evaluators. (C) 2009 Elsevier Ltd. All rights reserved.