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Passive House vs Net Zero BC's west coast

Passive House or Net Zero: Which is Right for Your BC Custom Home?

Over the past few years, Canada has been actively pursuing sustainable building practices to mitigate the environmental impact of its construction sector. Two prominent approaches to green building in BC today are Passive House and Net Zero. Both are significantly more energy-efficient and sustainable than a typical home built to the British Columbia Building Code 2024, but each with its distinct objectives.

What is the BC Energy Step Code?

The BC Energy Step Code is a voluntary provincial standard that came into force in April 2017 to provide measurable, performance-based energy-efficiency increments to achieving more energy-efficient buildings in British Columbia. Builders are encouraged to go beyond the requirements of the base BC Building Code, and local municipalities may voluntarily choose to adopt the steps into their bylaws and policies.

It consists of a high-performance staircase that represents increasing levels of energy efficiency. There are 5 steps for Part 9 residential buildings, with Step 1 representing the minimum improvement and Step 5 meeting the Net-Zero Energy Ready (NZER) new construction standard. As local municipal governments adopt higher steps, these policies increase the energy efficiency requirements for new construction in their communities, assisting the Province of British Columbia in reaching its target of all new buildings being net-zero ready by 2032. While adopting the BC Energy Step Code is currently voluntary, the province may in the future require certain Step Code levels to be met to comply with the BC Building Code.

Passive House

Passive House is a rigorous, voluntary standard for energy efficiency in buildings, that results in ultra-low energy buildings that require little energy for space heating or cooling. The primary principles of Passive House design aim to achieve exceptional thermal performance through a combination of insulation, airtightness, high-performance windows and ventilation systems. These features enable your home to maintain comfortable indoor temperatures without relying heavily on active heating or cooling systems, significantly reducing your energy consumption.

The 5 principles of the Passive House standard are:
Super-insulation: Passive Houses are heavily insulated to minimize heat loss and gain, typically exceeding standard building code requirements. The superior insulation provides a continuous thermal barrier between the air inside your home and the great outdoors.
Airtightness: Passive Houses are constructed to be highly airtight, reducing uncontrolled airflow and heat loss. They must meet the Passive House Institute standard, with a maximum of 0.6 air changes per hour at 50 Pascals pressure (ACH50), verified with an onsite pressure test.
High-performance windows: Triple-glazed windows with insulated frames are used to minimize heat transfer. Windows must be perfectly sealed to contribute to your home’s airtightness,
Heat Recovery Ventilation (HRV): Mechanical ventilation systems with heat recovery are installed to provide fresh air while capturing heat from the exhaust air. When you’re not recirculating the same air throughout your home you can expect to experience a reduction in shared illnesses.
Thermal Bridge-Free Design: Careful planning goes into eliminating thermal bridges through the framework, studs, and window and door casings, which are pathways for heat to bypass the insulation. Rigid insulation panels beneath the exterior cladding, and hollow window extrusions injected with polyurethane insulation, are two cost-effective ways to eliminate thermal bridging.

Net Zero Energy (NZE) standards

In BC we’re referring to homes built to the CHBA Net Zero Home Labelling Program, which takes a holistic approach to sustainability by aiming to produce as much energy as your home consumes over a year. Net Zero homes prioritize renewable energy generation on-site to offset the energy the household consumes for heating, cooling, lighting, and other operational needs. Energy efficiency measures are essential for achieving net zero, but the primary focus is on achieving a balance between energy consumption and renewable energy production.

Key features of Net Zero homes are:
Energy efficiency: Similar to Passive House, Net Zero homes incorporate superior insulation, airtightness, and efficient mechanical systems to minimize energy demand.
Renewable energy generation: On-site renewable energy sources such as solar panels or wind turbines generate electricity to offset your energy consumption.
Energy storage: Grid-tied systems with net metering, or optional battery storage systems, are often used to store excess energy generated during peak production periods for later use.
Energy monitoring and management: Advanced monitoring systems track your home’s energy consumption and production in real time, allowing you to optimize your energy usage and identify areas for improvement.

Similarities and differences

Environmental considerations

The West Coast’s Sea to Sky Corridor – from Horseshoe Bay through Whistler to the Pemberton Valley – offers some of the warmest and most temperate weather in Canada. However, the Passive House Standard works well in a wide range of climates, mild and extreme, and both cold and hot.

Whether it’s the winter chills of Fort Nelson, Dawson Creek and Burns Lake, the extreme summer heat of Lillooet, Oliver and Osoyoos, or the wide alpine temperature fluctuations experienced in Whistler’s alpine neighbourhoods, a well-insulated Passive House can be very effective in maintaining comfortable indoor temperatures while minimizing heating and cooling requirements. Achieving Passive House standards in extremely cold or hot climates can require additional insulation and HVAC capacity, which could potentially increase construction costs.

Like the Passive House Standard, Net Zero homes are designed from the ground up to be super energy-efficient. These homes are also airtight, super-insulated, with high-efficiency windows and doors, and smart design. It’s the solar panel system that’s the superhero of the net zero home, leveraging renewable energy to offset heating and lighting demands.

Cost considerations

High-performance Passive Houses and Net Zero Homes, once considered a luxury by many, are gradually being viewed as a way to future-proof our homes as building codes and legislation move us towards a greener future. Eco-friendly technology and building knowledge are becoming more widespread, with BC municipalities and builders voluntarily adopting Steps 3 or 4 of the BC Energy Step Code for Part 9 residential buildings.

The good news is that building a performance home is becoming increasingly more affordable, and the initial investment will come back in the form of much lower BC Hydro bills and a higher quality of life. Net Zero homes and Passive Houses are up to 90% more energy efficient than conventional homes built to code.

High-performance homes are built to a much higher standard. This can save you a lot in maintenance costs over the years. Airtightness, moisture control, superior continuous insulation, high-efficiency windows and doors, and state-of-the-art heating, cooling and ventilation systems make them more durable and resilient than code-built homes.

Building a custom Passive House or Net Zero home in the Vancouver and Sea to Sky communities currently averages between $450 and $600 per square foot, but can be even higher with the finest finishes and luxurious amenities.

Comfort and health

In addition to improving your building’s resilience, your high-efficiency home can improve your family’s health and comfort. Both Passive House and Net Zero buildings prioritize your comfort and health. The mechanical ventilation system continuously filters out pollutants, allergens, dust, and other contaminants from the incoming stream of fresh air, while exhausting the stale, contaminated air from kitchens and bathrooms and other areas. The airtight construction and improved ventilation also prevent moisture buildup and the growth of mould and mildew.

Passive House or Net Zero… or can you have the best of both?

While distinct design and building approaches, Passive House and Net Zero share fundamental principles, and these similarities complement each other. The Passive House standard can become the path to achieving the CHBA Qualified Net Zero Ready Home label, built to the very same efficiency requirements as a Net Zero home, but without the renewable energy solar panel system installed yet.

A synergistic opportunity presents itself when your Passive House-certified home’s energy efficiency measures have reduced your home’s energy demands so low it also qualifies as Net Zero Ready and only a small renewable energy source can cover its needs entirely. Then, whenever you’re ready, install the renewable energy solution and apply for Net Zero certification as well.

The takeaway

Both the Passive House and Net Zero Energy standards offer effective pathways toward sustainable and energy-efficient new home construction in British Columbia. While Passive House focuses on achieving exceptional thermal performance and reducing energy demand through insulation, airtightness, and mechanical ventilation, Net Zero Energy homes aim to balance energy consumption with on-site renewable energy generation.

Ultimately, the choice between Passive House and Net Zero Energy principles depends on project goals, budget constraints, and to some degree, municipal adoption of the BC Energy Step Code. Both standards represent significant strides toward reducing your household’s carbon emissions and promoting sustainable development while creating healthier and more comfortable home environments.

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