About 40% of the world's primary energy is used by buildings. This indicates that the bulk of greenhouse gas emissions are caused by buildings. In this investigation, the decrement factor (DF) and time lag (TL) of a new 3D-printed model are experimentally determined. It is really time to cut back on such energy consumption to lessen buildings' negative environmental effects. The introduction of new model 3D-printing blocks with high thermal inertia might be a way to lower the building's energy usage. Decrement factors and time lag are characteristics of thermal inertia. In this investigation, the decrement factor and time lag of a new 3D-printed model are experimentally determined. At the University of Salahadin's College of Engineering, a pilot house measuring 1 m x 0.45 m x 0.45 m is constructed specifically for this application. The equivalent temperatures of the inside (room one) and outside (room two) are used to determine the decrement factor and time lag. The findings indicate that using the new 3D-block model, the time lag is around 120 minutes, and the decrement factor is approximately 0.34. The 3D-printing block enables a 4.5°C reduction in the peak interior temperature. Since temperature changes outside are not noticeable, less energy is used to cool the structure during warm weather.