With global warming on the rise, many buildings, both commercial and residential, are being constructed using more sustainable and eco-friendly techniques. According to BetterBricks, buildings are responsible for approximately 40% of the total energy used in the United States and about 50% of Carbon Dioxide, or CO2, emissions. Dire statistics like these make it clear why reducing these numbers is imperative to maintaining the well-being of our planet. From rooftop and horizontal gardens on apartment complexes to home solar panels atop of homes, this blog post will examine some of the innovative ways in which buildings are becoming increasingly more sustainable and less harmful to the environment.
Net Zero and Carbon Neutral Buildings
The Net Zero Energy Certification is given to buildings that on an annual basis use as much energy as they produce. In some cases this means produce more energy than they use while other days they may produce less than they use, but over the course of a year their energy intake averages to zero compared to energy produced. This is a quality many sustainable buildings aspire to have because then they are not consuming excess energy produced by utility companies. However, Net Zero Energy buildings are not to be confused with Carbon Neutral buildings because they are not always one and the same. A Carbon Neutral building uses absolutely no fossil fuels to function and releases no greenhouse gas emissions. It uses clean, renewable energy which may or may not be produced on site. If a building uses as much renewable energy as it produces, then that building is likely both Carbon Neutral and Net Zero Energy, but this is not always the case.
Sustainable Building Materials
There are two factors that determine if a building’s materials are sustainable. One factor is if the materials are energy-efficient and they create a “tight envelope,” meaning they don’t let in elements like wind and rain and alternatively they don’t let out heat and air conditioning. The other factor is if the materials themselves are recycled or eco-friendly. One material gaining popularity is using steel as beams instead of wood. According to the Steel Recycling Institute, it takes about 6 scrapped cars to build a 2,000 square-foot house out of recycled steel compared to using 40-50 trees for wood. In addition, recycling steel takes 75% less energy than making new steel. Another material used to conserve energy is concrete molded between two layers of insulation. These concrete walls save about 20% of energy over traditional wood-framed houses. There is also a new plant-based polyurethane rigid foam on the market now called Pacific BioFoam that can be used very effectively for insulation, so it not only is the most eco-friendly urethane foam on the market, but it is also as effective as the others at insulating.
Two surprisingly sustainable and energy efficient building materials are completely natural: straw and mud. These natural materials have long been passed off as being primitive compared to more modern materials, but they Straw bales, a byproduct of grain, not only adhere well to plaster and stucco walls, but they are also excellent insulators. A straw bale house can reduce energy costs by 75% and they actually provide better fire protection as well as sound and pest insulation than conventional construction (like wood framing) because the bales are so tightly packed. Building with mud has been around for centuries but it is actually a very sustainable building material. Some of the benefits of mud houses are they are very low-cost, extremely durable, and they naturally insulate themselves to be warm in the winter and cool in the summer. Rammed earth homes are very popular because they can be designed very beautifully at a cheap cost. Rammed earth (which is the compression of mainly sand and clay into dense walls) is a wonderful energy-saving building material for arid climates, like that of New Mexico, and it is extremely fire-resistant, chemical-free, and pest resistant.
Many people by now have heard about LEED, or Leadership in Energy and Environmental Design, and seen the LEED certification in buildings here and there, but it is a certification that every architect and engineer of buildings should strive for. The LEED Certification is given to buildings in varying degrees depending on how conscious they are of both the environment and humans, meaning how well the buildings provide comfort for their occupants while also limiting their effects on human and environmental health.
Some energy-conserving systems within a building or home are dual-flush toilets which can save up to 80% of toilet water consumption, furnishings and carpets made from recycled materials, EnergyStar certified lightbulbs which use 70% less energy than regular bulbs, and efficient duct and faucet systems with no leaks for air or water.
Looking to the Future
In the future, I think it would be good to see many of these techniques combined to build the most sustainable houses and buildings possible. Buildings need to increasingly produce their own energy though the use of solar panels and wind energy and also need to conserve their energy through the use of sustainable, insulating materials. As an architectural engineering major, I hope to incorporate many of these techniques into home and office design in my future career and construct the greenest buildings of which we’re capable.