Abstract
This study is regarding the evaluation of envelop thermal performance in the very cold region and proposes an evaluation method, which includes all of the evaluation processes ranging from building envelope load to energy consumption. The proposed evaluation method of optimized envelope thermal performance is applied to an actual office building in Ulaanbaatar, Mongolia. Finally, building's annual envelop load, cooling heating load and energy savings rate have been calculated after revising glass and window ratio. The method of study is, (1) to identify external environmental conditions through climate analysis, (2) to set a baseline model that satisfies the basic conditions of ASHRAE 90.1 (3) to calculate envelope load, heating cooling load and energy consumption (4) to propose two alternatives, (5) to provide quantitative analysis of the building's cooling and heating load with the revised envelope and the amount of energy savings through energy simulation.