SmithGroupJJR: Chesapeake Bay Foundation, Brock Environmental Center

New construction of an educational facility; office building

By SmithGroupJJR August 17, 2015

Engineering firm: SmithGroupJJR
2015 MEP Giants rank: 28
Project: Chesapeake Bay Foundation, Brock Environmental Center
Address: Virginia Beach, Va., United States
Building type: Educational facility; Office building
Project type: New construction
Engineering services: Automation, controls; Electrical, power; Fire, life safety; HVAC, mechanical; Lighting; Energy, sustainability; Plumbing, piping
Project timeline: 3/1/2012 to 12/15/2014
MEP/FP budget: $2,139,803

Challenges

The Chesapeake Bay Foundation (CBF) wanted to create the Brock Environmental Center in Virginia Beach, Va., to implement its advocacy, restoration, and education efforts in one location, but this also necessitated appropriate environmental goals. Their goals are to protect, preserve, and celebrate this setting, creating a design of its place, while simultaneously showcasing innovative technologies that contribute to net zero energy, water, and waste.

The project is pursuing certification with  U.S. Green Building Council LEED-NC v.2009 (targeting LEED Platinum) and the Living Building Challenge v.2.0.

Energy efficiency: The center is predicted to be net zero energy, a significant benchmark for design as we near 2030.

Indoor air quality: Provide the occupants with as much outside air as possible.

Water reduction: The center is truly net zero water and will become possibly the first in the U.S. to receive a commercial permit for drinking treated rainwater in accordance with federal requirements.

Solutions

Energy efficiency: To achieve net zero, the design takes advantage of passive measures and meets the resulting demand using high-performance equipment and controls. A central water-cooled variable refrigerant flow (VRF) HVAC system uses 18 ground-source wells, harnessing the earth’s stable temperature, improving heating and cooling efficiency. The VRF system is coupled with a dedicated outside air system. Occupancy/vacancy sensors control lighting, ventilation, and plugs (reducing “vampire” loads). Energy Star copiers, computers, appliances are used throughout. These measures alone result in a remarkably low EUI of 15.5 kBtu/sq ft/yr. This resulting energy demand is met and exceeded by grid-tied, on-site renewables. Two 10-kW wind turbines, predicted to generate 84 MMBtu/yr, book-end the center located to minimize turbulence as well as site disturbances. A 38-kW photovoltaic array, predicted to produce 126.6 MMBtu/yr, is located on south facing roofs. Small battery backups maintain emergency lighting, security, and composter exhaust for multiple days to withstand most power outages. This asset, when combined with the passive design measures that maintain a comfortable setting without reliance on power, provide passive survivability for both Chesapeake Bay Foundation (CBF) and the Ocean Park community.

Indoor air quality: The center uses natural ventilation and daylighting to provide lighting and passive cooling for all public spaces (excluding restrooms; mechanical, electrical, and plumbing rooms; and storage areas). Bi-directional breezes are captured with low inlets and high outlets on both north and south facades. Airflow modeling predicts the building can effectively maintain comfort using only natural ventilation for 11% of the year. When sensors determine climate suitability, mechanical cooling shuts and automated controls send an e-mail to staff alerting them to open windows, using a combination of hand-crank and motorized operators. Motorized windows allow night-flush of the interior to precool the interior during cooling-driven months. During hours when there is not climate suitability, all mechanical systems have been designed to achieve minimum ventilation as required by ASHRAE Standard 62.

Water reduction: Two standing seam metal roofs capture rainwater, filling two 1650-gal cisterns, enough to withstand 23 days of drought. Rainwater is filtered (four log filters) and disinfected (ozone and UV, chlorine was subsequently added and CBF is appealing this requirement), and supplies all water uses within the center. Composting toilets reduce water demand while also treating waste on site. Solid compost is used on site, while leachate is stored and sent to a local struvite reactor and converted into commercially available fertilizer. Greywater from sinks and showers is piped to a greywater rain garden (raised above sea level) that treats the water allowing it to infiltrate. Excess roof runoff is diverted to raingardens that naturally filter and infiltrate runoff, managing all stormwater on site. All hardscape is composed of permeable pavers and gravel, with adjacent raingardens and bioswales to treat runoff, allowing for infiltration.