This paper attempts to extend its impact analysis of indoor cooling temperature control to all types of buildings, which currently is only the obligation of public buildings under the Rational Energy Utilization Regulations, using Global Change Assessment Model (GCAM). Once the updates of building sector information for GCAM with its base year of 2005, model simulations are conducted for the cases of indoor temperature control of 18°C, 26°C, 28°C, respectively. Cumulative impacts expected up to 2030 since 2015 are 173.2 MTOE, USD 64.4Bil., 360.5 MTCO2 for primary energy consumption reduction, energy import reduction and CO2 emission reduction, respectively for the case of 28°C. Considering the fact that this amounts to 64.6% of total energy imports of 2013, it is recommended to reform the current indoor temperature regulation being extended to commercial buildings with properly designed incentive structure.