Green buildings prioritize environmental concerns by limiting energy use, water consumption and pollution emissions. Some may even turn to cleaner alternative energies for powering their operations.
Life Cycle Assessments (LCAs) allow us to consider the effects of building materials and equipment from birth-to-death. Studies indicate that people living and working in buildings designed sustainably report higher satisfaction with their indoor environments as well as increased self-reported productivity.
Energy Efficiency
Buildings account for an enormous share of global carbon dioxide emissions and energy, water, and material consumption – providing one of the greatest opportunities for improvement. Green buildings reduce energy demand through improved insulation, air tightness, lighting/HVAC systems that minimize resource waste as well as using renewable sources instead of traditional fossil fuels to power them; some even generate their own power on site!
Sustainable features offer many direct benefits to both owners and tenants of green buildings. Owners and tenants alike can save money through lower energy and water costs, reduced maintenance expenses, more efficient structures, healthier indoor environments that promote employee productivity and reduce absenteeism due to asthma, respiratory allergies or stress; in turn reducing environmental impact helps build more resilient communities to climate change.
Water Efficiency
Green buildings seek to maximize energy, water and materials efficiency through adopting various practices and technologies – including those related to renewable sources like solar and wind power – that aim at maximizing these metrics.
Innovative technology such as bifacial solar panels and Trombe walls that capture daylight during the day and release it later can reduce dependence on traditional energy sources while simultaneously increasing energy independence and decreasing carbon footprints of buildings. These developments help lower dependence on traditional sources and foster independence of energy production while at the same time decreasing carbon footprint.
Buildings account for 14% of US potable water consumption; designers can significantly lower this figure by selecting native and drought-tolerant plants, installing self-sustaining irrigation systems and employing water-saving appliances.
At the core of designing green structures is conducting an in-depth cradle-to-grave assessment known as life cycle analysis (LCA). LCA provides an integrated approach that takes into account aspects such as embodied energy use, global warming potential, resource consumption and pollution impacts; often included as part of certification systems such as LEED, Green Star or Living Building Challenge certification systems.
Materials
Construction is one of the world’s most polluting industries due to embodied energy (the amount of energy it takes to make materials like concrete). Green buildings reduce this impact by using eco-friendly and sustainabile materials in construction.
These include lumber from sustainably managed forests, low-carbon concrete, repurposed glass and natural insulation such as sheep’s wool. Also intriguing are living materials which contain biological compounds whose growth serves a practical purpose – for instance self-mending concrete that uses bacteria to strengthen and fill cracks.
Green buildings also rely on cleaner energy sources to power themselves, such as solar panels on roofs or water-saving fixtures and landscaping to reduce stormwater runoff, all while helping mitigate its effect on local wildlife and ecosystems.
Indoor Air Quality
Occupants of green buildings tend to report higher levels of satisfaction with indoor air quality (IAQ) compared with those living in conventional structures, although evidence for these claims can vary significantly and is somewhat tenuous.
Many construction materials, furnishings and products emit chemicals that can negatively impact Indoor Air Quality (IAQ). Selecting low-emission paints and furniture reduce off-gassing while moisture-resistant materials help prevent mold growth that contribute to poor IAQ. IAQ can also be improved through proper circulation of fresh outdoor air through ventilation systems.
Climate changes can also have an effect on IAQ in green buildings. Elevated outdoor temperatures may increase ozone concentrations, leading to reactions that produce pollutants indoors. Changes in precipitation patterns can alter flooding, droughting droughting wildfires and pest populations resulting in negative IAQ in these structures.
Recent research comparing IAQ in green and non-green low-income homes concluded that residents perceived superior IAQ in green buildings; however, this result was not statistically significant due to previous research largely focused on subjective evaluations of IAQ without concurrent environmental conditions analysis.