Sustainable Design: Buildings We Can Live With
Green building has become a buzzword of late. Open any trade publication, construction journal or design manual and you’re sure to see some reference to sustainable design. Those who have just begun to pay attention to this market trend may ask, what exactly is green building, and how does it affect our industry?
According to Gary Kuzma of Hellmuth, Obata + Kassabaum Inc. (HOK), a design firm world-renowned for its commitment to sustainable design, "Green building is an environmentally and people-friendly solution to a living and working environment."
Alan Scott, director of consulting services at Green Building Services of Portland, Oregon, echoes this interpretation. "Green building is building that includes aspects of sustainable design with the goal of reducing operating costs and environmental impact," he said.
The Office of the Federal Environment Executive defines green building, in essence, as the practice of increasing the efficiency with which buildings use resources and reduce building impacts on human health and the environment.
Green building elements can range from orientation of the building to minimize solar impact, to high-performance glass, to energy-efficient lighting and on-site cogeneration of power supply. Green building is making the greatest impact in commercial, institutional and multi-family housing sectors. According to Kuzma, director of mechanical, electrical and plumbing engineering at HOK’s Houston office, there has been little impact in the industrial sector as yet.
Taryn Holowka, media contact for the U.S. Green Building Council (USGBC), an organization that promotes environmentally responsible buildings, agrees. "The program was originally created for the commercial sector, and that’s where we’re seeing the most activity," she said.
However, sustainable design influences the insulation industry indirectly, since energy conservation is a large factor in green building. Improving a building envelope’s energy efficiency is a key component to overall energy conservation, and one cost-effective way to do that is to increase the amount of insulation, said Kuzma.
Insulation is one of the tools that can be used to attain energy efficiency. Depending on the client’s project location, insulation can become an even more important factor. Thermal insulation may have more of an effect in a Minnesota winter or a Phoenix, Arizona, summer than it does in a city like San Diego, California, which enjoys mild year-round temperatures, said Kuzma. In most of the United States, increased insulation is a cost-effective way to gain on energy efficiency.
When increased insulation improves thermal performance, it helps a project earn LEED (Leadership in Energy and Environmental Design) credits for bettering the energy efficiency of the building. A project receives credits toward certification if it goes above the industry standard baseline for commercial buildings–ASHRAE Standard 90.1. Apart from the building’s envelope, insulation is also present on ducts and pipes, although the LEED credit is wrapped up in the whole of energy efficiency.
The USGBC’s LEED Green Building Rating System is a voluntary national standard in which construction and renovation projects earn credits toward certification as sustainable buildings.
The original LEED classification applies to new construction (NC); in this scenario the building owner is in control of both core and shell and tenant spaces, and is working to certify the building as a whole. The levels of certification (depending on the number of points the completed project receives) are certified, silver, gold and platinum. Points can be earned for a myriad of accomplishments: for using recycled content materials; for reducing design energy cost by 15 percent or more; for recycling or salvaging 50 percent or more of the construction and land debris waste; or for using materials from local sources.
Other LEED credits include the utilization of water-efficient landscaping (some sites plant drought-resistant trees that do not need watering); incorporating low-emitting paints, carpets and adhesives; and designing the building so that 75 percent of tenant spaces are exposed to daylight.
Altogether, there are more than 50 items in six categories that offer points toward certification. However, earning them can be a challenge–only seven of the 188 LEED-certified buildings nationwide have earned platinum status.
In addition to LEED-certified NC, there are three new programs for the commercial sector. LEED for existing buildings (EB) addresses specifics for existing buildings that are in need of facility and operational improvements. It’s a set of performance standards for the sustainable operation of existing buildings, according to Kuzma. It covers building operations and system operations in existing buildings where the majority of the interior and exterior construction is to remain unchanged.
"The EB program has to do with renovation, not necessarily of commercial interiors, but of HVAC systems, plumbing systems or things other than what the tenants actually see.
"Commercial interiors (CI) addresses specifics of tenant spaces, primarily in office, retail and institutional buildings where there are tenants occupying spaces. For example, a developer builds a building and seeks to bring in tenants to occupy that building. The spaces that are occupied by the tenants are covered by the LEED CI designation," said Kuzma.
Finally, core and shell (CS) basically addresses new core and shell construction, encompassing the base building elements–the structure, the envelope and the central systems like HVAC, plumbing, etc. It recognizes that there is division between the owner and the tenant for certain elements. It’s intended to evaluate building projects where the owner is not in control of the interior design and setup of tenant spaces.
Additionally, the USGBC is currently developing guides for sustainable design that will apply specifically to non-commercial structures such as healthcare facilities, schools and campuses, laboratories and retail locations.
Companies who have implemented green building are seeing benefits in three areas, which Kuzma refers to as "P cubed: People, Planet and Profits." One of greatest benefits is increased employee productivity, thanks to better working environments.
"There have been many studies done in recent years that have shown that buildings with these improved environmental qualities actually result in better people performance. People are sick less, are at work more, and tend to perform better if they’re comfortable.
"If you can improve the productivity of the people that occupy your building, let’s just say arbitrarily, half of a percent in one year, it will more than cover the increased cost of the ventilation effectiveness or improved lighting–the paybacks are almost instantaneous. If you look at the salaries, and their benefits, what people cost versus what buildings cost, it’s dramatically different. People cost so much more. Just making a small impact on improving people performance is huge on the bottom line," said Kuzma. This is one of the biggest selling points of sustainable design for companies who need to be convinced it’s a good idea.
LEED-certified buildings also have a gentler environmental impact, and help to reduce the depletion of natural resources through both construction and their life-cycle phases. Promoting environmental stewardship is very important to many large
companies’ public reputations, and they want to achieve LEED
certification in part to let the public know that they are keeping the environment in mind.
And finally, there’s the bottom line–an important consideration in uncertain economic times and in view of record-high
energy prices.
"If a building is more energy-efficient, costs less to maintain and uses less water, all of which are savings in annual operating costs, which contribute to lower life-cycle costs, it makes financial sense," said Kuzma.
With so many important benefits, what’s stopping people from doing green building? It seems the challenge to getting LEED certified is probably not much different than any other project–providing the best end product within budget and on schedule.
"If there’s any challenge with getting LEED certified, it’s the process. There’s paperwork to fill out, a process that has to be followed. It’s a very process-driven methodology in implementing the sustainable design objectives you feel are important. It’s important to have a team of professionals that have that experience," said Kuzma.
"It used to be that the difficulty or challenge was finding a project team that has the experience with the process of getting certified. But today, that’s no longer the case. There are a lot of people in construction, a lot of owners, a lot of design professionals who are educated and versed in LEED.
"It’s not hard to find a team of people who promote it, or people who are good at it, but it’s even better to have a team who wrote a book on the subject," said Kuzma.
Despite the challenges and notwithstanding the perception of the construction industry as one that’s initially resistant to change, the USGBC reports a high level of interest in its LEED-certification programs.
"The trend is growing very fast," said Kuzma. "Some project types faster than others, some owner types faster than others, some design firms faster than others. Within HOK, it is not a trend. It’s what we consider a standard of care that we try to apply to every project for every client. To me, fundamentally, that’s what it has to be for it to be successful."
In addition to the 188 buildings currently LEED-certified in the United States, another 1,794 projects are registered with the USGBC program and are seeking certification.
"This growth is much higher than we anticipated," said Holowka. "About 5 percent of new commercial construction is green building, totaling 215 million square feet of space." For a program only 5 years old (it was publicly launched in 2000), that’s quite an accomplishment.