A comfortable work space is important to produce productive work performance among workers. In Malaysia, the condition of office environment and its related issues on thermal comfort are fairly new. Past studies shown that the increment of energy consumption in high rise offices tend to increase dramatically. This is because the consumption of air condition for cooling accounts in office buildings had increased from 40% to 60% in recent years and the total electricity usage for office units also rises intensely due to urban heat island (UHI) resulted from modification of land surfaces. The objective of this paper therefore is to investigate the conditions and problems of existing prominent high rise office in Kuala Lumpur which is IBM Plaza and Menara Mesin Niaga in the scope of thermal comfort as well as describes an integrated passive design approach to reduce the cooling requirement for high-rise office building through an improved building envelope design using green technologies like external wall cladding following the GBI standard. This paper also attempts to get the user perception towards their existing workspace. For this purpose, case study as research strategy is adopted using mixed methodology combining qualitative and quantitative method under the framework of interpretivism and positivism research paradigm. Findings indicate that external wall cladding made of composite aluminium provides much advantages to the user. This study is important because appropriate design principles by adopting appropriate building envelope made of suitable material addressing ecology issues will not only provide a comfortable living environment to the users but also established referential guideline for future designers and scholars whom interested in office design.