Green Building Design and Major Renovation Guidelines for Government Offices

Abstract

The Department of Public Works and Town & Country Planning (DPT) has determined to increase the role of the government sector to mitigate climate change problems and environmental systems, where buildings contribute partially to these problems. DPT, therefore, aims to establish green government office design guidelines for new construction as well as major renovation. The study method was done via reviewing green building rating systems in Thailand and other countries, establishing a green building rating tool, testing the tool with selected buildings and calculating the cost increase in addition to value for money. Two buildings were selected as case studies, one was a new building with classical Thai style, and the other an existing office, where both were considered extra large buildings according to the building construction code.

         To observe design issues that needed correction in order to pass the green building criteria, a post-occupancy survey was conducted in the existing office. It was found that the Thai classical style building was able to pass the prerequisites as well as any other contemporary style building. However, its high-sloped roof hinders some criteria from being achieved such as the installation of solar ready roofs, the collection of rainwater from roofs, and the reduction of urban heat island effect from the roof.

         Modification of the ventilation system was required by both the new and existing building in order to meet the minimum ventilation rate criteria. The Thai classical style building especially needs to have an appropriately placed intake and exhaust air grills on the exterior wall or roof for both mechanical and aesthetic concerns.

         The new building design is made of 72 criteria, 32 prerequisites and 40 option credits, with contents concerning site selection, project administration, master planning, building design, construction, operation and maintenance. On the other hand, the major renovation includes 26 criteria and 42 credits. All prerequisites must be met in order for the building to be considered as a DPT green government office building, if the building can also achieve more than half of the total option credits, it will be considered as a DPT high-level green office building.

         The cost increase to establish a new green building was about 2 % and 4% to adapt an existing building. For the high-level green building, the increase was about 8% for the new building, and 7% for major renovation. However, it is worth mentioning that the standard green building has better value for money than the high-level green building. DPT has made all design criteria for both new construction and major renovation available as e-books through their website.