This work aims to present and evaluate different techniques to reduce energy consumption in residential buildings under the climatic conditions of Jeddah city, Saudi Arabia. The study was conducted on a residential building with an area of 250 m2 and an energy demand of 370 kWhm−2 for cooling. The proposed techniques include several techniques including the use of four different types of thermal insulation and different thicknesses from 50 to 300 mm. It also includes the effect of using thermal insulation on the wall or in the ceilings. It also includes studying the effect of the type of windows used and window areas compared to wall areas. The energy demand of buildings using the proposed techniques is evaluated and compared under different conditions throughout the year. The building and the proposed techniques will be simulated using TRNSYS software throughout the year. The results showed that using double-glazed windows reduces energy requirements by 8.34% compared to single-glazed windows and reducing the window-to-wall ratio from 75% to 25% reduces energy demand by 1.43% to 3.08% respectively. Using thermal insulation on the exterior walls and roof reduces energy demand by 13.42% compared to insulation on the roof only. The maximum energy reduction was achieved with wall insulation with the roof at 21.41%.