pol house performance: courtyards, windows and variable space

This article takes the often-anecdotal example of a traditional pol house and puts it to the contemporary test with data loggers that monitor the thermal performance of three similar pol houses in Ahmedabad throughout the summer. It finds that when used as intended, the pol house performs well, as expected and often expressed! However, the introduction of contemporary patterns of movement, like privacy and fixed uses for rooms, restricts the performance of the house as a whole, which suggests that implications of new use patterns should be explored as avenues for innovation in the traditional typology.

research authors: Mihir Vakharia, Rajan Rawal, Yash Shukla, Agam Shah




jaali as a performative daylight device

This study analyses the Indo-Islamic jaali (stone latticed screen) for its daylight performance. The jaali reduces light admitted inside, cutting out its blinding glare; it allows the passage of air but arrests powerful gusts, which makes it an effective climate control device for various climates in India. 256 stone jaalis of 30 13th to 16th c. Islamic mosques in Ahmedabad were documented for frame size, solid/void ratio, and height-of-void to thickness (overhang ratio). The measurements were used to model and test the performance of the jaali, which revealed that the overhang ratios and depth of the jaali played an important role in blocking direct sunlight, providing uniform daylight, and preventing glare.

research authors: Dharmesh Gandhi, Vishal Garg, Rajan Rawal





trees every 250m reduce temperature

This study explores the role of surface materials on an urban micro-climate and the changing effects due to vegetation in the thermal climate of Gandhinagar, Gujarat. A CBD area is configured according to the rules of ground coverage, Floor Space Index (FSI) and site setback. Through the use of a three dimensional numerical computer model ENVI-met V3.4, the CBD area is analyzed for its micro-scale thermal interaction with urban environment. The results show that at a medium range density, trees effectively reduce ambient air temperature. Too sparse and the cumulative effect is lessened, but too dense and the foliage does not allow heat to escape. 

research authors: Jalpa Gandhi, Rajan Rawal



deeper daylight: anidolic ducts, shelves, and tubes

Deep plans have become a common practice in multi-storied building design. However, the deep core areas of these buildings cannot be naturally illuminated by windows on the facade, and therefore, such areas depend entirely on electricity for illumination. But this is not the only way. This article studies the use of daylight device technologies to enhance natural illumination in deep plan office buildings by exploring office typologies of New Delhi. Three daylighting devices available in the international market are addressed: light shelves, anidolic light ducts, and light tubes.

research authors: Neha Singhal, Tanmay Tathagat, Rajan Rawal




light and color: energy based design

We often look at reducing the energy consumption of lighting at the end of a project, when the light fixtures are selected, and when the basic design is ready. Daylight is considered as a factor in design development, but artificial light less so. This study examines the relationship between colour and artificial light levels, taking on a pure white and pure black room as two ends of the brightness spectrum, and then works toward the nuances of designing with optimum levels of light consumption and glare, given fixed colour scenarios.

research authors: Rohini Singh, Rajan Rawal




commercial courtyards: energy gained or loss?

Commercial buildings consume enormous quantities of energy, so there is a constant pressure to use design to address these shortfalls in performance. A common strategy is to borrow effective techniques from the past and apply them to contemporary construction, which does not always produce the desired results! This study looks at a classic example: the courtyard, and assesses to what extent courtyards could improve energy consumption within the limitations of building bylaws and varying site proportions of new master plans in Indian cities. 

research authors: Rachit Kumar, Rajan Rawal




daylight and visual comfort: a positive relationship

Performance criteria in design is often given in strict numbers, which defines a particular range of static comfort for a generic person. However, daylight is variable, and also a more preferred light condition. This study looks at the intersection of visual comfort and daylight, exploring whether when daylight is present, people—office workers in particular—are visually comfortable for a larger range of light levels than they would be in either exclusively daylit or exclusively artificially lit spaces.

research authors: Chaitali Trivedi, Rajan Rawal


CARBSE articles: Architecture & Energy

In this series of articles, Melissa uses the research of the Center for Advanced Research in Building Science and Energy (CARBSE), carried out with the help of students in the Master of Interior Architecture Design program at CEPT University, Ahmedabad, to look at aspects of energy research in the built environment through a variety of lenses—in studies that analyze traditional pol houses with scientific rigour, examine the optimized possibility of stone jaali performance, and explore simulation to assess courtyard effectiveness, among others. These have been published as part of a year long series in Indian Architect & Builder.