A review of traditional multistage roofs design and performance in vernacular buildings in Myanmar

• Main Authors: Zune, May, Pantua, Conrad Allan Jay, Rodrigues, Lucelia, Gillott, Mark
• Format: text
• Published: Animo Repository 2020
• Subjects: Roofs—Myanmar > Design and construction; Architecture, Ancient > Myanmar; Architecture and climate; Mechanical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/1701; https://animorepository.dlsu.edu.ph/context/faculty_research/article/2700/type/native/viewcontent
• Institution: De La Salle University

Myanmar's territory mostly experiences tropical monsoon climate, where temperatures are normally not extreme, but humidity can increase discomfort. In response, vernacular architecture strategies have evolved to deal with excess heat and humidity. One of the most prominent of these strategies is the use of high multistage roofs with ventilation. Over the years, many of the traditional buildings were altered but the use of multistage roof design has remained remarkably resilient in Myanmar. Nevertheless, little is known about their contribution to thermal comfort and their vulnerability to overheating risks due to the pervasive threat of the climate crisis. In the work presented here, a thorough review of multistage roof typologies was followed by an investigation of their performance when building parameters including form, ventilation and materials were varied. Twenty-four dynamic simulations were performed using three building typologies and thirty-two computational fluid dynamic simulations were performed using two building typologies. In all cases, indoor volumes were kept the same. The results suggest that with the use of a typical light-weight permeable envelope, the indoor temperatures follow outdoor ambient temperature closely; although a heavier-weight set of materials did not impact significantly on the maximum air temperatures, it has made a different with regard to the lowest temperatures and overall comfort. The variable that impacted the most on the results was roof ventilation mode, with the best results being 3.5 % of a year better than the worst. The multistage roof was found to help reduce heat gains form solar radiation. The findings showed that Myanmar's vernacular buildings with multistage roofs offer an opportunity to improve indoor comfort in tropical climates and therefore its ability to moderate indoor temperatures through the use of simple building physics and geometry should be honoured. © 2020 Elsevier Ltd