**6. Conclusion**

Circular economy of building materials can significantly preserve the embodied carbon which is not properly defined in building regulations yet. Therefore, further improvements to the building regulations are recommended to achieve the reduction target of building energy consumption. The relationship between operational carbon and embodied carbon should be considered from the early design stage as there is always a possibility of higher embodied energy during the optimization process of the operational energy. The properties of the building materials play a vital part in resource and energy efficiency in buildings. Hence, building material matrices are also recommended to develop continuously with new materials and follow regularly to select the building materials. This process will help to enhance the potentialities of circular economy in our building construction industries and reduce the consumption of primary resources and overall project cost as well.
