Modern Applied Science; Vol. 8, No. 5; 2014 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education 132 The Extent of Sunlight Penetration Performance on Traditional Style’s Apartment Façade in Putrajaya, Malaysia Ahmad Sanusi Hassan 1 & Yasser Arab 1 1 School of Housing, Building and Planning, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia Correspondence: Ahmad Sanusi Hassan, School of Housing, Building and Planning, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia. Tel: 60-19-506-8260. E-mail: sanusi.usm@gmail.com Received: July 10, 2014 Accepted: July 15, 2014 Online Published: August 27, 2014 doi:10.5539/mas.v8n5p132 URL: http://dx.doi.org/10.5539/mas.v8n5p132 The research is financed by Universiti Sains Malaysia. Abstract In this study the analysis is to measure the performance on the extent of sunlight penetration on front apartment facades. The apartments are located in Putrajaya, Malaysia. Putrajaya is the administrative city for the federal government, and it is considered the latest new city in Malaysia with postmodern style buildings which exhibit a range of complex geometric elements blending with colonial, modern and traditional architectural style. The scope of this study is to measure the extent of sunlight penetration on the apartment facades. Two front facades of the apartments were selected in the case studies using computer simulation for the analysis. The selected case studies are sixteen stories apartment located in Precinct 17 and seventeen stories apartment located in Precinct 18. SunTool software is used in the survey to calculate the extent of sunlight penetration. The survey will be conducted at a position when the sun path is perpendicular to the house façade. This analysis will compare results of the computer simulations of these two apartments in relation to the facade design of the architectural elements for shading devices. This study finds that the more the application is the traditional shading elements, the more is the shading performance on the façade walls. However this study also finds that traditional shading elements are designed only to block sunlight from horizontal angle of the sun position. They are not designed to obstruct sunlight from vertical angle of the sun position. Keywords: sunlight, traditional shading elements, penetration, apartment, Malaysia 1. Introduction 1.1 Problem of Direct Sunlight Penetration This study highlights problem of direct sunlight penetration to the interior area of apartment building and solar radiation on the apartment facade in tropical countries like Malaysia. Poor design integrated with shading elements which causes poor shading performance is the primary causes of the problem as the hypothesis of this study. This problem creates heat gain to the indoor area which causes low level on human comfort factor to the house occupants. The study on high rise apartment design is important because the building façade has a larger area with a tendency of exposure to direct sunlight compared to the building façade of low rise building (Ismail, 2002). As a result, design with excellent shading elements on the apartment façades is very critical. It is the objective in this study to verify the problem scientifically to dictate this design faults by measuring the extent of sunlight penetration on the apartment façade. Results of this study can be used as a guide for architects and those involved in the building industry to refer as issues to overcome solar radiation in apartment façade design. This reference provides awareness and guidelines for passive design with efficient usages of shading elements to avoid solar radiations in the tropical countries such as Malaysia (Bakhlah & Hassan, 2012). 1.2 Importance of the Problem The measurement will be calculated using either manual or computer simulation. This study is limited to the apartment design in Putrajaya which is the latest new town built in Malaysia with post modern building styles. It epitomizes the present and future direction of housing industry in Malaysia. One of the popular post modern styles is integration of traditional Malay architectural style. It is the aim of this study to measure effectiveness of the integration of traditional Malay shading elements in post modern apartment which are roof overhang,