There is a new national building code brewing in Canada that will drastically affect how we design, build and renovate housing. We have all seen and heard the various green-labelling programs over the years – those early adopters following a strict protocol to reduce the carbon input and output associated with our homes – R-2000, LEED and Energy Star, for example. Unless you are in the field, it’s tough to know the difference, and separate the green washing from the true four-leaf clovers of efficiency. For some time, depending on the province and city, there have been political commitments toward a certain green standard. This new building code, however, takes it one step further. Enter net zero.
What does this mean?
Net-zero homes, whether new or renovated, produce as much clean energy as they consume. They are up to 80 per cent more energy efficient than typical new homes and use renewable energy systems to produce the remaining energy they need. Every part of the house works together to provide consistent temperatures throughout, prevent drafts, and filtre indoor air to reduce dust and allergens. The result? Exceptional energy performance, the ultimate in comfort and a home at the forefront of sustainability.
OK, when do we do this?
Canada committed to being net zero as a nation by 2050. Seems like a long way away, but when the entire country currently runs on some form of fossil fuel, switching systems is a challenge, including converting our power grid to be bi-directional, with a significantly larger capacity than it currently has. Understandably, it’s become a political hot potato. Various provinces and cities have examined the feasibility of undertaking this change. Toronto, as an example, amped up the pressure by creating a target of 2040 to achieve net zero, so to put it bluntly, the time is now. The new national building code is set to roll out next year and will be more restrictive with energy requirements. If you are planning a project today, you should explore how to develop toward net zero, or net-zero ready.
How do we start?
If you’re planning a new build, or an extensive renovation to an existing home, work with a net-zero-trained designer and builder, such as Eurodale, to develop the plans and building specifications. The Canadian Home Builders’ Association (CHBA) lists member companies that are trained and certified in this. An energy advisor and HVAC and electrical trade specialist will also need to be at the table early on.
Steve Ramoul, from Home Inspectors Group, says the key is how the details are executed – working with an experienced team to identify which changes to conventional building practices will net out the biggest bang for the buck in terms of efficiency, without compromising on comfort, resiliency and health. Testing the execution via a blower door is how you separate the real green from the marketing wash.
So, what changes are we making?
Ramoul outlines six changes, in order of priority:
- Insulate: While we often think of interior applications, it’s the exterior insulation that makes all the difference and is critical to reducing thermal bridging.
- Draft-proof: Air sealing of ducts, vent penetrations, floor/wall/roof intersections and window and door openings. Blown sealing products such as aerobarrrier and aeroseal can help fill the voids where the trades miss their mark in the field before finishes are installed.
- Ventilate: Once the building is tight, ventilation is needed to control humidity and particulate levels. Indoor air quality is reliant on the efficient exchange of stale indoor air with fresh and temperature-controlled outdoor air.
- Heat pump. Air-source cold-climate heat pumps (CCHP) are older technology, but relatively new to Canada. With claims of being able to heat to -25 degrees C and much more efficiently in shoulder seasons than standard furnaces and air conditioners, this is what governments are hanging their hats on. Field experiences vary and our grid is currently only so reliable, so we prefer (a more costly) belt and suspenders approach of a back-up supplementary gas-fired heat option for cold winter nights or storm events.
- Upgrades to all appliances: The most efficient possible – induction cooktops, solar-fired hot water tanks – to replace old leaky gas appliances. This is a political soft spot.
- Windows and doors: This is the most confusing aspect of the changes, even for industry professionals. Even building-code-compliant windows can create disastrous conditions if not designed with care. Siting of the building, size of glazing, U-values, ER values, frame ratings versus centre-glass ratings, can all impact the comfort in these homes in both the heating and most critically, the cooling seasons. Don’t rush this selection and ensure you connect the window team with the HVAC designers as well as your net-zero-certified designer and builder to get it right. Failure to do so be costly!
Zero or ready?
Net-zero-ready homes are built to the exact same efficiency standards as net-zero homes. The only difference is that the renewable energy system (solar panels) have not yet been installed. However, everything has been designed and constructed to easily put the solar panels in place. Solar, while much cheaper today than even five years ago, is still a costly up-front investment to offset the power we use inside our homes. Plus, in Ontario, the current grid couldn’t handle all the power if we all installed panels on our roofs today. We suggest getting confirmation from the utility of connection capacity prior to shelling out for those panels.
Be the change
Whether you believe in global warming or not, if you feel solar and EV’s are no more environmentally sensitive than a conventional gas vehicle, or if you’re like me and feel your tinfoil hat reflects just enough rays to keep you cool, the building code is changing, and fast. We are going net zero, and it starts with getting net-zero ready!