Building envelope trade-off method integrated with BIM-based framework for energy-efficient building envelope

In recent years, the demand for energy-efficient buildings and green buildings has increased significantly in India. However, this surge has few hindrances, i.e. the absence of a centralised green material library, alterations in the later stage of design for certification and few energy certified buildings. This paper proposed a BIM-based workflow that mainstreams this surge of energy-conscious buildings' envelope using Building Envelope Trade-off Method (BETM) in the early design phase. BETM facilitates energy-efficient envelope through simpler calculations based on material thermal properties, orientation and surface area. A BIM library is modelled for commonly used materials and passive features. The developed workflow is demonstrated on a selected building complex, and its effectiveness is tested with a parametric simulation of 216 envelope combinations of different alternative envelope materials, orientations, and passive facade features. This result shows a similar envelope performance factor ratio for the considered orientations, whereas 0.35% and 12.49% reduction is observed in the corresponding peak cooling total load (PCTL) compared to the as-built case. The PCTL provides the necessary insight into building energy analysis considering its surrounding features. The developed workflow will ensure a better performing building envelope according to the Energy Conservation Building Code.