I had the good fortune last week to tour the Chesapeake Bay Foundation’s new Brock Environmental Center in Virginia Beach, where I was visiting relatives following the Greenbuild Conference. The building is not only one of the country’s leading examples of sustainability, but also includes a wide array of resilient design features.
Christy Everett, the executive director of this Hampton Roads Office of the Chesapeake Bay Foundation gave us an awesome tour, and my friend Greg Mella, FAIA of SmithGroupJJR, who was the project designer, principal in charge, and project manager for the building, filled in some details on the 10,500 square-foot building. The building cost was just over $400 per square foot and the total project cost $7.3 million.
Targeting Living Building Challenge certification
The Brock Center was completed in April 2015 as a second landmark building of one of the Mid Atlantic’s leading environmental organizations: the Chesapeake Bay Foundation (CBF), which is focused on protecting this ecologically sensitive waterway. In 2000, the organization completed a new headquarters building in Annapolis, Maryland, and that became the first building in the world to achieve a LEED Platinum rating—the highest designation in the LEED Rating System.
While LEED Platinum was the pinnacle of green building ratings in 2000, those boasting rights today are represented by the Living Building Challenge. CBF and SmithGroupJJR, set the Living Building Challenge (LBC) as a target early in the design process. The building is expected to earn LBC certification and has already achieved LEED Platinum certification.
Beyond the building itself, the project included protection of the 118-acre Pleasure House Point tract of land, saving this low-lying area on the Bay from a development plan that was to include 1,100 high-rise condos and townhouses. The City of Virginia Beach and the Trust for Public Land worked with CBF to purchase the property after the developer defaulted on loans in the economic downturn of 2008.
The intent of LBC is to eliminate the most significant environmental impacts of buildings. This is achieved through stringent requirements, including net-zero energy, net-zero water, avoidance of all fossil fuel use, and a prohibition of roughly 300 red list chemicals. LBC certification cannot be earned until a building has been in operation for a full 12 months and the energy and water performance is demonstrated.
The Brock Environmental Center has a 45 kW solar (photovoltaic) array on the roof and two stand-alone 10 kW Bergey wind turbines that are projected to generate more than 100% of its energy use. In the seven months since the clock started on the full year of operation needed for LBC certification (April 1, 2015), 90% more electricity has been generated than consumed by the building!
With shorter days of winter approaching, the building may well begin using more energy than is produced, but the building is on-track to maintain a positive balance sheet on an annual basis, according the Mella. The wind turbines are projected to contribute about 40% of the electricity and the solar panels 60%. While for the first five months, wind production was running at only around 30%, production is up this fall and Mella expects to end the year with the 60-40 split.
When Hurricane Joaquin affected the East Coast the first week of October 2015, the two wind turbines, which were selected for their ability to withstand hurricane-force winds, generated 1,761 kilowatt-hours (kWh) in five days, nearly a month’s worth of electricity consumption for the building, according to Mella (see graph). During that five-day period, the Brock Center’s solar array, generated just 325 kWh. “I’m glad we diversified our portfolio of on-site renewables,” Mella noted.
The ability of the building to operate on a net-zero-energy basis is enabled, to a large extent, by its superb energy conservation features. Walls are insulated to R-35, the floor of the elevated building to R-31, and the roof to R-50—more than double typical levels for this climate. Windows are triple-glazed with low-e coatings and argon gas-fill, providing R-7. To meet the durability ratings required for this coastal location, the designers had to go with European windows, which Everett noted was disappointing to them; they had hoped to source windows more locally—required by the LBC if such products exist. The modeled energy use intensity (EUI) of the building is a remarkably low 15.5 Btu/sf·yr.
Heating and cooling are provided by a variable-refrigerant-flow (VRF) system with 18 300-foot-deep wells providing the heat source and heat sink. The system differs from a typical water-source heat pump system by having a central condenser, rather than a condenser in each unit; the refrigerant is piped to each VRF unit in the building. While the energy source for the VRF system is electricity, the heat pump technology means that in the heating mode, much more usable heat is produced per unit of electricity consumed than would be the case with electric resistance heat.
Natural ventilation is a key component of the building design, which includes a dogtrot design feature that is common in vernacular architecture of the Southeast—a narrow section of the building footprint across which cooling breezes can be channelled. Precise orientation and careful design for shading also helps to control solar heat gain. To minimize solar heat gain, there are no west-facing windows.
The building employs extensive use of daylighting. In fact, on the day when we visited, Everett wasn’t even sure where to turn on the lights in a main entry area. “We generally leave the lights off,” she told us. It was a rainy, gray day during our visit, but we didn’t feel the need for electric lighting in most spaces.
Only rainwater is used in the building
One hundred percent of the building’s water, including all potable water, is provided with rainwater harvested from the roof. This water, which is captured after a first flush is diverted during a rain event, is stored in two 1,650-gallon tanks in an insulated area beneath the building. This may be the first public building with a permitted system meeting federal standards that allows harvested rainwater to be the sole water source.
Purification of the rainwater is provided with filtration, ozonation, and UV-treatment. Currently, the water is also treated with chlorine (a red-list chemical in the LBC), but the hope is that the chlorine treatment can be eliminated once purity of the water is demonstrated to the satisfaction of regulatory officials. Drinking from one of the water fountains in the building, I wasn’t able to taste the chlorine.
The building has been using about 50 gallons of water per day, says Everett, below the predicted 145 gallons. Consumption is so low primarily because only composting toilets are used. The building was projected to be able to have enough stored water to handle a 23-day drought, but with consumption running well-below that, the building should do all right in a significantly longer drought.
The small amount of humus produced by the composting toilets will be applied to a designated area of the site. Graywater from sinks and a shower flows into rain gardens.
A healthy building
Avoidance of harmful chemicals, superb ventilation, and other features contribute to the Brock Center being a very healthy building to work in. Approximately 25 staff people work in the building, though a lot are involved in educational programs, so it is rare for all 25 to be there at the same time.
Chris Gorri, the facilities manager at the Brock Center, told me that the staff are happy in the new building. Benefits of the healthy materials used in the building have led to a few surprises. He described an experience during allergy season this year when a staff member who suffers from severe allergies was visiting from another CBF office. “She said that usually she would have to take medicine to prevent a serious headache,” he told me, “but before she knew it, she had been at the Brock Center for several hours and she felt better than she had felt all week.”
Resilient design at the Brock Environmental Center
Many of the above-mentioned features, including the very high-performance building envelope, natural ventilation, and daylighting, contribute to the building’s resilience. In the event of an extended power outage, the building would almost certainly maintain habitable conditions, even during the heat of summer or the coldest winter conditions.
During the one major power outage the building has experienced since it opened, Gorri said that in walking into the building “you wouldn’t even have known we didn’t have power; the building was naturally lit and extremely comfortable.”
Given the coastal location and risk of hurricanes, significant attention was paid to protection against high winds, storm surge, and flooding. The building is elevated 14 feet above sea level—exceeding the 500-year FEMA flood elevation and, according to CBF, accounting for projected sea level rise over a reasonable time horizon.
The building is also designed to withstand 130 mph winds, which exceeds requirements in this area. The curved roof design and metal roofing contribute to the wind resilience.
A key resilience feature is that the building will do just fine should something happen to Virginia Beach’s municipal water supply or wastewater treatment system. Being able to deal with human waste is a huge concern during disasters, and it is rare for a building to deal with this so completely. While the composting tanks are under the building, provisions have been made to secure them to the foundation during flood events and maintain functionality.
Durability is aided by the zinc shingles on the roof, deep overhangs that protect the building, and naturally rot-resistant cypress siding.
Where the Brock Center could do better, relative to resilience, is with back-up power. Small battery back-ups maintain emergency lighting, security, and composting toilet exhaust for multiple days during power outages, but this battery back-up is minimal. There are currently no provisions to maintain true functionality during power outages.
With both solar and wind contributing to the facility’s net-zero-energy performance, it would not be too difficult to modify the system to serve the building’s operating needs during power outages. Currently, the renewable energy systems here, as with the vast majority of such systems in the U.S., are net-metered through the local utility company and include neither batteries for storing electricity nor specialized inverters that can function even if the grid is down.
According to Mella, there has been some discussion about adding batteries in the future to take the Brock Center entirely off the grid. “This will be so much easier to do now because we have a really great understanding of how Brock consumes and produces energy,” he told me.
Had the recently announced LEED pilot credits on resilient design been available when the Brock Center was in design, I suspect that there would have been more consideration of back-up power. The rest of the credit suite would have been easily achievable for the project.
In fact, it wouldn’t take much for the Brock Center to be able to serve as a resilience hub for the area—providing a place where residents could charge their cell phones during a power outage, fill up a water bottle, and use restroom facilities.
# # # # #
Along with founding the Resilient Design Institute in 2012, Alex is founder of BuildingGreen, Inc. To keep up with his latest articles and musings, you can sign up for his Twitter feed. To receive e-mail notices of new blogs, sign up at the top of the page.