• Dekar Wangchuk Department of Electrical Engineering, College of Science and Technology, Phuntsholing
  • Tshewang Lhendup Department of Electrical Engineering, Jigme Namgyel Engineering College, Dewathang
  • Gom Dorji Department of Electrical Engineering, College of Science and Technology, Phuntsholing


wood wool slab, thermal transmittance value, site energy, source energy


This work presents a comparative energy performance analysis of building wall materials, namely, hollow concrete brick and wood wool slab (WWS). Based on the functioning of a real-time residential building apartment, the geometry of an apartment is designed in SketchUp and modeled using the OpenStudio plug-in software tool. The net energy performance scenario of hollow concrete brick and wood wool slab are discussed in detail for three principal climatic regions of Bhutan videlicet hot and humid subtropical regions (Phuntsholing), the cooler temperate (Thimphu) of central mountain regions, and the alpine tundra regions (Gasa). The considerable amount of net site energy, net source energy, and annual energy use intensity (EUI) was reduced in wood wool slab walled apartments compared to the hollow concrete brick construction material. The net site energy was reduced by 122.2 kWh, net source energy by 444.4 kWh, and the energy use intensity was decreased by 1.7 kWh/m². Notably, the HVAC energy consumption of wood wool slab apartments is less in all three climatic zones than that of hollow concrete brick apartments. The overall reductions are 453.95 kWh, 122.86 kWh, and 1255.57 kWh for alpine, temperate, and subtropical zones respectively. It is mainly due to the lower thermal transmittance and low thermal conductivity of the wall materials. From this study, it is observed that wood wool slab houses can provide a better indoor environment with less amount of annual energy demand. Therefore, the wood wool slab can be the best alternative low-energy building material in the Bhutanese construction industry.


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How to Cite

Wangchuk, D., Lhendup, T., & Dorji, G. (2022). ENERGY PERFORMANCE COMPARATIVE STUDY OF WOOD WOOL SLAB AND A POPULARLY USED BUILDING MATERIAL IN BHUTAN. Journal of Applied Engineering, Technology and Management, 2(1), 31–40. Retrieved from