Preservation of architectural heritage is a top priority of every sustainable development strategy. The idea is to create a healthier world by lowering environmental effects on architectural heritage by means of inventive, rapid and cost-effective options to eco-renovating heritage buildings. Conservation practices and initiatives must adhere to the historic current fabric, including its applications, connections, and values. These approaches must be focused on an enhancement strategy to reduce negative effects of environment on historical buildings. Lebanon is facing a slew of environmental issues as a result of poor environmental management, especially in the historic built environment. For this reason, the study will review the relationship between architecture and environment, discussing sustainable architecture, green buildings and its characteristics, and sustainability and architectural heritage conservation. Moreover, the study also explores architectural heritage and high-performance buildings, clarifying the impact of environment on architectural heritage, high performance buildings and their design objectives and characteristics. The study focuses mainly on quality techniques and high performance buildings, presenting quality in architecture aspects and Six Sigma as a quality improvement technique for enhancing performance of existing buildings. In this sense, we will shed some light on various attempts of green buildings and reduction of environmental impact on architectural heritage in Lebanon. The study proposes a new methodology as a performance improvement approach for converting the historical building into a high-performance one. The paper also emphasizes the role of sustainable development implementations to conserve the architectural heritage, while optimizing performance characteristics of historical buildings, using Six Sigma technique as enhancement strategy to achieve high-performance for historic buildings in Lebanon.