The codes for sustainable homes have been introduced to drive a step-change in green building practice. It set the international standards for key elements of the design, construction and planning. It is a tool for designers and structural engineers and real estate developers and users. This paper reviews the concept of sustainability codes through some of the world's leading experiments and implementation mechanisms . In order to reach the main points for each codes and to find out what is essential and what is linked to the characteristics of the region, this paper also present a brief explanation for the codes and limitations imposed on the building through the evaluation process in the international codes. The paper also explained degrees of classification and its effectiveness on a building, whether its binding or optional.