Trial / Demo
As part of the Green Buildings graduate course at KKTM Sri Gading, this academic project used IES Virtual Environment (IESVE) to optimise the orientation of a proposed Program Perumahan Rakyat Termiskin (PPRT) housing design, enhancing energy efficiency and indoor comfort.
One of the key strategies to maximise energy efficiency and comfort was to consider the building orientation, which plays a crucial role in minimising solar heat gain and maximising natural ventilation. To reduce heat absorption, large wall surfaces facing east and west were strategically avoided, where solar radiation is most intense in the daytime. Instead, the window-to-wall ratio to limit heat penetration was optimised, ensuring adequate daylighting. In order to harness natural ventilation, more openings were prioritised on the north and south facades, taking advantage of Malaysia’s prevailing wind patterns to enhance indoor airflow and thermal comfort.
Using IESVE’s SunCast application, a detailed solar radiation analysis was conducted, visualising the impact of sunlight exposure on different building surfaces. This enabled the building’s orientation and fenestration strategy to be refined to achieve an optimal balance between thermal performance and daylighting efficiency.
In line with Malaysia’s MS2680:2017 standard (Energy Efficiency and Use of Renewable Energy for Residential Buildings) Code of Practice, the daylighting performance of the PPRT house was validated using the IESVE FlucsDL application. The results demonstrated that the design fully complies with MS2680:2017 requirements, with over 90% of the room areas achieving an ideal daylight factor of 1.0% to 3.5%. This ensures well-lit interior spaces that minimise reliance on artificial lighting, further reducing energy consumption.
To complement the findings, IESVE’s fisheye real-view simulation in RadianceIES was used, offering a realistic perspective of the daylight conditions inside the house during daytime, without artificial lighting. This immersive analysis provided valuable insights into how daylight dynamically interacts with interior spaces, reinforcing the effectiveness of the passive design approach.
Through IESVE MacroFlo simulations, the effectiveness of natural ventilation within the proposed design was analysed. The results confirmed that prevailing winds facilitate adequate airflow, ensuring a continuous exchange of fresh air throughout the indoor spaces. The simulation was conducted under a 50% window opening condition, demonstrating the capability of the design to optimise passive cooling strategies.
Further refinement was conducted using IESVE MicroFlo-CFD simulations, which provided a detailed assessment of indoor airflow distribution. The results indicated that the air velocity throughout the house remained within the MS2680:2017 recommended range of 0.25 m/s and below. This air movement level ensures thermal comfort without causing noticeable drafts, except in areas of lower temperatures, where airflow visualisation through cigarette smoke traces movement.
An essential aspect of thermal performance lies in the wall material selection, where two primary construction types were evaluated:
1. Wet construction (high thermal mass walls):
2. Dry construction (low thermal mass walls):
To further assess occupant comfort, the Predicted Mean Vote (PMV) was analysed for both wet and dry construction scenarios. The findings indicated:
Based on the simulation results and thermal comfort analysis, the proposed PPRT house design utilises dry construction to optimise occupant wellbeing. Although it experiences slightly higher daytime temperatures, this aligns with times when occupants are typically at work.
At night, the lower indoor temperature significantly enhances comfort, reducing reliance on cooling systems. This passive design approach not only ensures sustainability but also minimises energy consumption, reinforcing the principles of an energy-efficient and climate-responsive residential building.
The optimised PPRT housing design prioritises energy efficiency and occupant comfort through passive design elements like building orientation and natural ventilation. Ultimately, the final PPRT design used dry construction to maximise occupant wellbeing and minimise energy consumption by effectively employing IESVE performance modelling software.
"Through detailed simulation and analysis with IESVE, we were able to design a PPRT house that works with the Malaysian climate, offering comfortable airflow and maximising nighttime comfort with its dry wall construction, all while minimising energy use."
- Najib Bin Hanapi, Graduate Student in Green Building, Kolej Kemahiran Tinggi MARA (KKTM) Sri Gading
