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LOW CARBON, LOW COSTS Warehouse Tenants Minimize Heating Bills By Mark Hutchinson A 65,000-SQUARE-FOOT warehouse in Dartmouth, Nova Scotia, earned Canada’s first certification for Zero Carbon Building Design (ZCB-Design) in the fall of 2019 as part of the Canada Green Building Council’s (CaGBC) pilot program for the zero carbon standard. East Port Properties, the developer and manager of the five multi-tenant buildings that comprise the Wilkinson Warehouses, leveraged experience delivering energy-efficient projects to demonstrate the potential for a lower-emitting industrial sector. East Port President Judy Wall took up the challenge, building on the company’s track record as the developer the first multi-tenant warehouse in Halifax to be certified under the LEED program more than 10 years ago. Warehouses have traditionally been designed as a lowestcost product, especially since developers don’t always know what the building’s final use will be or how that usage might change over time. However, developers like East Port are seeing an increased demand for sustainable real estate and are creating a market for smart spaces and value-add property management services. Signing on to the 15-building CaGBC pilot program is part of that effort. By 2030, Canada has vowed to cut greenhouse gas emissions by 30% below 2005 levels. CaGBC created the ZCB to support that process. It combines design and performance certification; measures the carbon balance of a building; and makes carbon reductions the key indicator for building performance.
The East Port team knew the key elements that would have significant impacts on building energy use: reduced air leakage; better insulation; efficient heating systems; and automated controls to reduce dependence on human intervention to operate the system. The building design started with a tight and well-insulated building envelope. The insulation value of the roof was upgraded to R-40, and then built using airtight, insulated, tilt-up concrete sandwich panels for continuous R-20 insulation value. According to Wall, one of the prime spots for heat loss is at the loading docks. Verticalstoring dock levelers, a product typically used in cold storage warehouses to keep the cold inside the building, were used to further reduce air leakage. A central in-floor system supplies heat via air-to-water heat pumps. This central heating system consists of six air-to-water heat pumps and a peak-load/back-up condensing natural gas boiler that provides a constant f loor temperature of 17⁰ Celsius. Electronically commutated motor circulator pumps in single-bay zones drive hot water distribution. Overhead unit heaters, metered and billed directly to the tenant, supply additional heating. Controls were installed to stop in-floor heating circulators from running in areas with open overhead doors. East Port also installed a net-metered solar photovoltaic system through Nova Scotia Power’s Net Metering program. The system is sized to offset the cost of fuel sources — assuming a heating energy intensity of 1.6 equivalent kilowatt-hours per square foot. With these heating considerations, it
would be possible for tenants to realize a no-cost central heating bill if they were vigilant to limit how long their overhead doors remain open. The efficiency of the design was especially apparent during an eight-hour power interruption, when it was -15⁰ Cs outside, but the indoor temperature dropped only 0.5 degrees. Going beyond the Zero Carbon standard, East Port opted for some features not typically found in a warehouse, such as Solera windows and skylights to maximize the use of daylighting. The buildings are also equipped with automated, energy-efficient ventilation systems and LED lights with motion sensors. While that translated into an approximate 10 to 15% cost premium compared to the Zero Carbon standard, East Port is now seeing a return on that investment. Higher net rents are achieved from tenants seeking lower heating energy bills and more comfortable workspace. A second warehouse has since been certified and construction is in progress on a third also targeting the standard. In addition, East Port is pursuing ZCB Performance certification. Performance certification proves the project’s operation has earned zero carbon emissions over a one-year period, as required by annual verification. zz Mark Hutchinson leads the Green Building Programs at Canada Green Building Council (CaGBC), including overseeing the LEED and Zero Carbon Building Standard certification programs. For more information, see the website at www.cagbc.org. Canadian Property Management | October 2020 21
