Green Buildings have become a definite solution to the climate change. While the concept dates back to several centuries, it is only now that both builders and homeowners are taking it seriously. The aim is to minimize the exploitation of natural resources and the means are varied. Saving electricity by the use of maximum daylighting, rainwater harvesting, better home insulation, use of solar power are some of the ways that the concept of building designing is changing in the recent years. While that’s a step forward, it is also necessary that we track the performance of our green designs. It’s just like we going to the doctor for regular routine checkups to ensure a healthy lifestyle and make necessary changes.
Green buildings, by definition, are self-sustaining and environmentally responsible by the virtue of their design, operation, construction, maintenance and even de-construction. Tools for measuring energy efficiency have become common (in fact, it readily shows on reducing electricity bills). However, electricity shouldn’t and isn’t the only determinant here. Things like waste water management, deployment of environment-friendly materials in construction, sustainable sit planning such that the natural habitat around is not destroyed are more complicated but crucial factors that need to be measured. It is self-explanatory that a ‘green building’ might not be performing as intended after a period of time and consequently ceases to be rated as “green”. This is where regular evaluation and performance tracing comes into the picture.
Challenges In Measuring Green Building Performance
Several facets come into play when it comes to measuring the performance of a green building, thus making it a complicated task.
Conceptual challenges: Firstly, any building designed to be “green” needs to list that factors that make it so. It is the lower energy consumption design; it is the low environmental impact of the construction or is it the long-term sustainability of the building? The task also boils down to listing the social, community, and health benefits that the building design promotes.
Practical challenges: The blueprints of ‘green buildings’ might not adhere to the standards after the construction is complete. It is necessary to understand and measure the difference between the actual and the modeled performance. Operational performance of the building should be more crucial than the design (theoretical) performance.
The availability of data, against which a green building is ranked, is another huge challenge among developers, especially in a terrain like India that is gradually adopting “green” standards. The benchmarks for a definitive comparison should result from continuous improvements, modifications, and renovations. The above depends highly on the expertise and experience of the architect with the project.
Green Home Performance – What to Measure?
So, what all constitutes the performance of a green building?
Energy, as in Energy Star Rating is the most common way of optimizing the performance of a green home. We already have the idea of appliances like air conditioners accompany various standards of energy star rating. Similarly, the performance of homes too can be monitored. According to the US Environmental Protection Agency, an Energy Star home is at least 15% more efficient than homes that adhere to the IRC (International Residential Code) standards. Further, these homes integrate energy saving fixtures (LEDs, Energy star rate appliances) to make it20-30% better performing. LEED Certification is another way of measuring the performance of green buildings.
Water efficiency measures the amount of water used in processes like HVAC, cooling towers, washing, restrooms, pantry, irrigation and others. The aim is to measure the amount of portable water used in the building process and consequently offer the building a ranking.
Wastes include any natural resource that isn’t optimally used and discarded by the building. This includes rainwater and electricity waste among other things.
The means of transportation used by the occupants is another determinant in the building’s health. Carpooling and using public transport is a way to optimize transportation, thus helping in both saving money and reducing the amount of pollution added to the environment.
- Human Experience
Lastly, it is about how healthy an occupant feels in the complex. This requires the monitoring of air quality, green space, and inflow of natural light among other things.
Measure It Correctly
It is highly crucial that the performance of the above factors is correctly monitored for a beneficial evaluation. While the standards of rating are different under various norms, energy audits need to be truly measurable. Green ratings vary significantly with the amount of space, number of people, internal load of the building, surface to volume ratio and other things. Thus, performance monitoring needs to be put in the correct perspective.
With the growing significance of climate change, it makes sense that we adopt ‘green’ standards of living. While this really comes with a change in attitude, the first step to practicality is honesty in our rating systems and standardization.
Curated by editor at Wienerberger India