. This paper evaluates the thermal performance of non-autoclaved aerated concrete (NAAC) produced with crushed waste glass bottle aggregate and glass fiber. A total of six different mixtures, including the partial substitutions of normal sand with waste glass sand (WGS) (0%, 15%, and 30%) and glass fiber (1%, 2%, and 3%), were designed. After the compressive strength and thermal conductivity (λ) of each NAAC mixture were firstly determined, the potential of NAAC to improve the thermal performance of student residential buildings was assessed. The energy-saving effect of NAAC was simulated using Autodesk Revit software tools in two different cities, Nur-Sultan in Kazakhstan and Boston in the USA. Moreover, annual heat loss was calculated. Test results present that the increase of WGS and glass fiber contents leads to increasing compressive. Interestingly, while increasing WGS content in the mixture decreases λ, increasing fiber content increases λ despite a slight variation. The lowest annual heat loss was obtained from the mixture containing 70% normal river sand, 30% WGS, and no glass fiber. 70NS-30WG-0GF. Finally, the energy performance simulation result indicates that NAAC used in a residential building leads to significant energy savings compared to normal concrete and brick structure.