This work is about the software named BEP-TR (Building Energy Performance -Turkey), which is developed upon request from Turkish Ministry of Environment and Urbanization to apply BEP-BUY to the BEP-IS. BEP-IS is an internet based software which is under the control of the ministry. BEP-IS confirms the calculations made for the building using the received project file and initiates the process of preparing EPC. BEP-IS provides users who takes part in this process interfaces designed as web pages. Users and their authorizations are managed by fully authorized users defined for the ministry through BEP-IS. Besides BEP-IS