With the backsliding of the current federal government, state governments, local jurisdictions, and private businesses need to do more to forge ahead in addressing climate change. The building industry is a big contributor to greenhouse-gas emissions (GHG). It is also conservative and slow to change. Many construction innovations and new building products, however, are in either the research, prototype, or early adoption phase. A few examples are:
- Pre-cast “self-cooling” concrete walls incorporate scalloped or deeply fluted exterior surfaces. A car radiator is similar — lots of surface area for wind to pass over and remove heat. A building project in Houston combined these grooved walls with reflective white paint, which also repels dirt. Vertical fin walls were added to the exterior as well as shade-giving plants on the sunny side. Monitoring showed interior temperatures 18 degrees Fahrenheit cooler than in nearby buildings with standard flat walls. The result: less cleaning, lower maintenance, reduced energy bills, and greater comfort for residents, with only a slight increase in construction costs. Society gets fewer GHG emissions and electrical grid pressure relief.
- A transparent window coating uses applied quantum physics to outperform conventional heat-reducing coatings. Multiple refractive indices inside stacked ultrathin layers collectively transmit or reflect light based on wavelength. The application is like polarized sunglasses, but unlike sunglasses, the coating remains clear and effective no matter the angle of incoming light. During heat waves, 87 percent of heat gain in our houses is through windows. This new coating blocks heat-producing ultraviolet light and infrared rays but not visible light. Tests of this wide-angle spectral filter coating yielded temperatures 13 degrees Fahrenheit lower than conventional glass. This coating can also be applied to car windshields and sunroofs. Comfort is improved with less energy demand.
- EcoSmart gypsum wallboard (GWB) uses 25 percent less water to fabricate, produces 20 percent less CO2 emissions, weighs 20 percent less, and saves 20 percent of fuel during transportation. EcoSmart 5/8-inch Type X board has a slight increase in cost — 7 percent — but has already captured about 35 percent of market share. It is considered cost competitive because installers love the reduced weight. Concerns about acoustic and fire-resistant properties, both of which depend on density, turn out to be unfounded. Tests show performance equal to standard 5/8-inch GWB.
To avoid big temperature swings, buildings incorporating passive solar design strategies rely on material with high thermal mass. Concrete is one such widely used material. A double layer of 5/8-inch GWB performs equally well, is less expensive, and a better choice for multi-storied structures harnessing natural heating and cooling technologies.
Speeding up our adoption of these and other innovations in sustainable building materials could greatly reduce carbon emissions not just in the building sector but overall.
