Code Green: New Standards Cover More Than Just Energy
Energy codes marked the start of a revolution when they were introduced in the 1970s in response to the energy crisis. Today, they are a regular part of building codes. But a new generation of building codes aims to go beyond just regulating energy use.
The aim of the new codes, such as Standard 189.1-2009 — developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the U.S. Green Building Council (USGBC) and the Illuminating Engineering Society (IES) — and the International Green Construction Code (IGCC) from the International Code Council, is to give building owners and facility managers guidance on how to build and operate a sustainable building, not just an energy-efficient one.
While they do contain energy provisions — ASHRAE 189.1 requires roughly 30 percent more efficiency than ASHRAE 90.1-2007 — they aren't limited to energy. Instead, they encompass a more holistic approach that covers everything from kilowatt hours to using graywater for landscaping.
Dennis Stanke, the chairman of ASHRAE's Standing Standards Project Committee 189.1, says the codes reflect how much goes into a sustainable building.
"A high-performance green building does more than just reduce energy use per square foot," Stanke says. "For example, it also reduces water use, it reduces heat island effect, it reduces storm water runoff. It has good daylighting. It has shading so that the good daylighting doesn't result in increased solar load."
The new codes also are designed to be usable by municipalities as comprehensive green building codes, which is a departure from previous code's that only dealt with energy. The codes give municipalities, for the first time, standards written in mandatory language as opposed to guidelines such as in LEED.
International Code Council (ICC) staff architect Allan Bilka says the change in language was needed to drive real change in building and renovation.
"In early 2009, on Earth Day, we had a green building focus group where ICC invited a number of interested parties to talk about a green building code," Bilka says. "What we came away with was we needed something that code officials could enforce. What we're saying is there are certain things that should be done if a building is to be called a green building."
A handful of governing bodies have already adopted the codes in some form, with most of them doing so on a voluntary compliance basis. (Because the IGCC allows for use of ASHRAE 189.1 as an alternative compliance path, adopting the IGCC essentially means municipalities have the option of adopting 189.1 as well.) In May 2011, the state of Maryland adopted the IGCC as a voluntary compliance option; the state of Oregon has also done so. Rhode Island has adopted the standard for state-owned buildings. Cities such as Scottsdale, Ariz. and Richland, Wash. also have adopted the IGCC as a compliance option. The U.S. Army announced in December that it would adopt ASHRAE 189.1 as its standard for all construction.
With the codes written in enforceable language, it makes it easier for communities to go green quickly.
"For new communities just starting out (with green), it makes sense to go right to the IGCC," says Anthony Floyd, Scottsdale green building program manager. "Why reinvent the wheel?"
The codes do, of course, have a heavy emphasis on construction. But they also deal with operating the building as well, which, as Brendan Owens, USGBC vice president for LEED technical development, points out, is critical to sustainability. That's especially important when it comes to energy — a high priority, given the need for action on climate change.
"You can't build your way out of an energy problem," Owens says. "You have to operate your way out of it."
It's not only green building codes that are demanding new levels of energy efficiency. ASHRAE 90.1-2010, for example, aimed to beat the 2007 version of the standard by 30 percent. The tougher approach to energy efficiency will affect many elements of the building, including lighting, HVAC and controls.
Lighting has seen a drastic increase in efficiency since conservation became a primary concern for facility managers. As a consequence, there is a limit to how much further lighting codes can go, says Bob Horner, Illuminating Engineering Society director of public policy.
"We can't just keep cranking the bar lower and lower," Horner says. Going to the point where "we're all wearing miner's hats," becomes a productivity and safety issue.
But the new codes still offer guidance on how to tackle lighting. While most of them are pretty straightforward — things such as occupancy sensors with manual on and automatic off controls or controls for outdoor lighting — a couple of options require a bit more planning.
"The first thing I would consider in a new building is, how much can I take advantage of daylight?" Horner says. "That's one of the single most important new construction techniques you can take advantage of right now."
As Jim Edelson, senior project manager with the New Buildings Institute, points out, taking advantage of daylighting is an old concept that just hasn't been used much until recently. As he says, even the cavemen took advantage of natural light, so why shouldn't building designers?
For buildings that are limited in how much daylight they can harvest, looking to other areas is necessary to see real savings in lighting. And there are plenty of ways to bring yourself up to compliance even if you can't take advantage of natural light.
Efficient lamps and ballasts can help. So can controls, especially ones that are integrated more tightly with building controls.
"There typically could be more done in the control arena," Horner says. "The most efficient lamp is one that's turned off."
Taking another look at areas such as hallways helps, too. "Hallway lights are often on 24/7 in a building and you don't need them on if no one's there or there's no traffic," Horner says.
And there's one more potentially surprising way to cut costs in the lighting area: Give employees more individual control over the task lighting in their workspaces.
"If people have personal control over their lighting, they actually tend to lower it more than you as a building designer might," Horner says. "Studies have shown that when you give people personal control over their environment, they tend to be quite energy conscious."
Both the IGCC and ASHRAE 189.1 are perfectly clear that if a facility manager hopes to be in compliance, HVAC systems are going to require some pretty heavy-duty controls.
In fact, the IGCC lists 10 different scenarios where a building's control system must be capable of automatically reducing peak cooling or heating demand by "not less than 10 percent."
So HVAC systems have come a long way in terms of what is a reasonable expectation. But while HVAC systems aren't quite the resource hogs they used to be, Edelson says they have a ways to go.
"HVAC has become considerably more sophisticated in terms of systems, but the problem with building codes is they're subject to federal preemption," he says. "Because of that, it's been a ceiling on the amount of efficiency we can find in the HVAC portion on the commercial building stack."
Federal preemption prohibits states from having more stringent standards than the federal government on products the latter regulates. That, says Edelson, means restrictions when designing codes and standards.
"The state of California Title 24 can't mandate efficiencies on rooftop units that are any more efficient than what are found in federal standards," he says.
Preemption does not mean there's no room for innovation. Because the federal government standards regulate individual pieces of equipment, not the entire system, there are opportunities for energy savings in different HVAC areas. Standard 189.1 tackles this by requiring, as one example, two-speed or variable-speed ventilation fans on "all constant volume DC units with a capacity greater than 110,000 Btu/h" and all fan coils with more than five horsepower motors.
The standard also takes advantage of advances in controls with requirements such as controls that throttle back HVAC and turn off plug loads in empty hotel rooms.