Research to develop building performance evaluation in the green building marketplace of India

05 Feb 2020

Research to develop building performance evaluation in the green building marketplace of India

The green building movement in India is booming. The Indian Green Building Council (IGBC) states that India has the second largest registered green building footprint - with over 7 billion square feet - and over 5,424 projects registered for green building ratings (as of September 2019). However there is little evidence about the actual energy and environmental performance of green buildings and occupant satisfaction with their design and indoor environment.

The Learn-BPE project

The two and a half year UK-India Newton Fund sponsored Learn-BPE project by Oxford Brookes University in collaboration with CEPT University (India), brought together the disciplines of building science and social science, to develop, test and refine, for the first time, a customised building performance evaluation (I-BPE) approach for the Indian sub-continent.

The project built upon several years of research on building performance evaluation (BPE), pioneered by OBU’s Low Carbon Building Research Group. Drawing from research on BPE in the UK and internationally, the I-BPE framework is designed to operate in the context of Indian building industry – which has less documentation of design decisions, more freedom during construction, fewer tested and certified products, less formalised building operation, and limited access to the costly equipment required for performance evaluation. The integration of BPE in architectural and educational curricula in India was demonstrated through workshops, summer/winter schools, classrooms-based courses and masters level dissertations.

As academia is considered to be an initial primary outlet of BPE, a survey of experts is conducted to investigate the drivers and barriers for implementing BPE-based methods in educational curricula. The expert survey reveals the lack of trained people for teaching BPE as a key challenge to its adoption, implying that trained people are needed as much as frameworks.

I-BPE framework

The I-BPE framework (as in Table 1) includes five ‘need to know’ elements covering technical and non-technical aspects of building performance. These are:

  • Review of design intent through design documentation and interviews with the design and construction team
  • Technical building survey, covering inspection of the building fabric, energy systems and controls
  • Energy assessment using annual energy bills/meter readings, monitoring of utility meters, sub-metering and monitoring of individual plug loads
  • Measurement of indoor environment, using spot measurements of internal and external temperature and relative humidity (RH), to continuous monitoring of specific variables, such as volatile organic compounds
  • Occupant feedback using a questionnaire, diary, interviews and focus groups, to assess occupant comfort, perceptions and experiences of the indoor environment.
Each of the study elements adopts a graduated approach, from Level 1 to 4. Level 1 is the basic method to implement the BPE element and higher levels are added for deeper investigation.

The I-BPE framework was applied to ten green-rated building case studies covering 193,375 square metres (seven offices, one educational and three residential developments) located in different climatic zones of India. The BPE studies identified ways to improve performance and benefit owners where the actual performance falls short of expectation.

Moreover the review of design documentation showed that the expected performance goals for the case study building – set by the green rating systems – were primarily focused on asset performance, covering building geometry and system performance, and did not directly address the operational aspects, such as setpoints, mode of operation (mixed mode) and occupancy schedules. The differences between asset and operation may be of greater significance in the Indian context because of the greater variability in the way buildings are operated. Differentiating between asset and operational performance will help the data to be analysed more effectively, and lead to more appropriate corrective measures.

The BPE case studies have also helped to build trust in the industry, which is currently shy of exposing themselves to liability risk resulting from actual building performance.

Scaling-up BPE in India

In a rapidly developing country like India, there should be a heightened sense of urgency for a widespread adoption of BPE, which will likely need to happen in both formal education and building industry symbiotically, ideally driven by both policy (energy code) and market transformation (‘green’ rating systems).

This is why the Learn-BPE project has promoted the integration of BPE in India through the formal educational system of architecture and engineering (A&E), and training of industry professionals through a continuing education approach. This will help to produce a new cadre of building performance evaluators who are competent across a relevant range of technical and social aspects of building performance. A national building performance evaluation network (I-BPEN) in India is being developed by Oxford Brookes University with partners in India to address this need.

The final report of the Learn-BPE project is available here and the I-BPE framework has been published here.

The Chartered Institute of Building Services Engineers (CIBSE) has written and published an article in the CIBSE journal on the Learn-BPE project, which is available here.

Professor Rajat Gupta of the Oxford Brookes Low Carbon Building Research Group has led a pioneering UK-India research study to develop and nurture adoption of building performance evaluation (BPE) in the booming green building marketplace of India.