Tun Abdul Razak Complex building as shown in Figure 1 had almost 40% of the building envelope consist of windows. Thus, the building management is planning to conduct window renovation works to improve the energy efficiency of the building. The renovation company had proposed two windows design that could reduce the Overall Thermal Transfer Value (OTTV). As a Registered Electrical Energy Manager (REEM), you had been assigned by the building management to evaluate which window design could help improve the energy efficiency of the building. Details on the building construction data and proposed window design are given in the next page. You are required to conduct detail calculation of the overall building OTTV for the existing window, window design 1 and window design 2 by using Microsoft Excel and by referring to the latest standard MS1525:2019. Conclude on which window design is better for energy efficiency improvement Figure 1: Tun Abdul Razak Complex building Tun Abdul Razak Complex building as shown in Figure 1 had almost 40% of the building envelope consist of windows. Thus, the building management is planning to conduct window renovation works to improve the energy efficiency of the building. The renovation company had proposed two windows design that could reduce the Overall Thermal Transfer Value (OTTV). As a Registered Electrical Energy Manager (REEM), you had been assigned by the building management to evaluate which window design could help improve the energy efficiency of the building. Details on the building construction data and proposed window design are given in the next page. You are required to conduct detail calculation of the overall building OTTV for the existing window, window design 1 and window design 2 by using Microsoft Excel and by referring to the latest standard MS1525:2019. Conclude on which window design is better for energy efficiency improvement Figure 1: Tun Abdul Razak Complex building