In 2011, the Nova Scotia Community College (NSCC) built a house on its Middleton Campus in the Annapolis Valley. No one lives in this house, and more likely than not, no one ever will. It’s a living laboratory where students are schooled in the finer points of sustainable building design, more educational than it is practical.
“It’s over-engineered,” says Scott Henderson, a faculty member with the NSCC’s School of Technology and Environment. Built over a decade ago, it was crammed with all the bells and whistles of the time: a heat pump, an in-floor radiant heating system, a rooftop solar array, a solar thermal water heater, a residential battery storage pack, an outdoor Electric Vehicle charging station and, of course, an EV. The house is flush with Energy Star appliances and produces way more power than it consumes. They christened it “Pilikan House,” using the Mi’kmaq work for “new.”
When built, many of Pilikan’s features were relatively novel in Nova Scotia. Heat pumps weren’t nearly as ubiquitous as they are today — nor half as reliable — and solar panels hadn’t yet become as commonplace as they are now throughout the Maritimes. It’s been instructive, said Henderson, to watch these technologies evolve relative to the older designs preserved in Pilikan, as well as to each other.
As an example, the building’s solar thermal hot water heater — which pumps water to a panel on the roof to be directly heated by sunlight — was significantly more cost-effective than heating water via Pilikan’s solar voltaic panels. But now, in 2024, most solar voltaics can heat water much more efficiently and affordably than their solar thermal counterparts. The panels on Pilikan manage 230 watts each, a healthy figure for 2011, but less than half the output of a standard panel today.
Nova Scotia has caught up with Pilikan House in several ways, at least in terms of panel and pump, but this living laboratory’s greatest asset remains largely unadopted across the Maritimes — simultaneously the home’s subtlest feature and by far its most consequential: the building “envelope.”
“This is the part of the building that separates the inside from the outside,” says Henderson. “And we need to design them better in Nova Scotia.”
Canada is a “heating climate,” he notes, and the ability of our walls, windows, and doors to absorb and retain heat is the single most important factor in building efficiency. Pilikan addresses this in several ways, perhaps most importantly through its envelope — inspired by the work of the Passivhaus Institut in Germany. Harnessing physics and building science, the standards of the Passivhaus Institut revolve around building houses which require little or no active heating and cooling for their residents to remain comfortable. Doing so is remarkably straightforward.
First, Pilikan’s walls are double studded and staggered, with the outer 2X4 studs misaligned with the inner 2X4 studs by eight horizontal inches. Between these very well insulated layers of stud (two distinct walls, effectively) is an unbroken, three-inch layer of cellulose. At no point do the two studs meet, which prevents “thermal bridging,” a direct line of uninsulated material (in this case wood) connecting the inner and outer walls through which heat might escape. It also means the building is airtight.
Pilikan’s orientation and windows make up the rest of its exceptional envelope. The leading wall faces south (rather than the road) and on this wall is a collection of triple-glazed windows, with argon gas between each pane and a reflective coating for infrared radiation, encouraging this invisible wavelength of light to enter, but not escape. All of this allows Pilikan to passively absorb and retain the sun’s heat, doing more to keep the building warm than any of its hardware.
“This building’s envelope is passive by definition,” says Henderson. “There are no moving parts, no electronics. It just sits there and works, simple, but boring.”
If you take an average from the literature, says Henderson, homes built with this calibre of passive envelope — thick insulation, no thermal bridging, a southward orientation, and windows capable of harnessing the sun’s heat — cost between 20 to 25 per cent more to build than equivalent homes without, but they enjoy a reduction in total energy consumption of over 90 per cent. He adds that we spend a lot of power on heating and cooling, so much so that many of these passive features have become standard in building codes across Europe, though not yet in Canada.
“Canada’s 2020 building code is like a baby step in the direction that we need to be going if we’re serious about mitigating the climate change impacts of our buildings,” says Henderson.
The insulating power (R-value) of Pilikan’s walls in r44, he says, whereas Nova Scotia’s current building code (the province hasn’t yet adopted the 2020 National Building Code of Canada) is closer to r17. Even when it comes to renovating old buildings, says Henderson, enormous reductions in energy consumption can be achieved by prevented thermal bridging and increased insulation, even when the structure cannot be reoriented south with triple-grazed windows. Their envelopes should be “Pilikanized” long before solar panels are bolted to their rooves, he stresses.
“In a hierarchy of green technology implementation, we should always start with the least complex and least energy intense technologies, like insulation,” he says. “Once that’s achieved, only then should you start thinking about putting in more electronically and mechanically complex technologies.”
The Climate Story Network is an initiative of Climate Focus, a non-profit organization dedicated to covering stories about community-driven climate solutions.
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