A study related to 'a multicriteria lifespan energy efficiency approach to intelligent building assessment' is presented. The IB Index is one example of a comprehensive tool, regarding buildings assessment. The IB Index is supported by ten modules, which broadly describe about intelligent buildings. Besides this, a technique, called The Analytic Network Process (ANP), can help decision-makers to measure intrinsic relations among indicators so as to facilitate knowledge reuse in assessment. The Energy-Time consumption/use Index (ETI) is a quantitative measurement for selecting indicators by means of an embodied energy consumption rate. ETI is used to evaluate indicators for the assessment of intelligent building. These assessment methods enable designers to compare different solutions and depict how well the social, environmental and economic issues can be balanced.