Designing new net zero homes, and retrofitting older homes to achieve net zero, is a pathway to achieving energy efficiency through sustainable design, by combining cutting-edge technology, sustainable design principles, and renewable energy systems. Net zero homes are designed to produce as much energy as they consume, resulting in net zero energy consumption.
Introduced in 2008, the BC Energy Step Code gives designers and builders the option to use either a prescriptive or performance approach when complying with the code’s efficiency requirements. Buildings must meet specific requirements under the approach, for sealing the building envelope, installing superior insulation and high-efficiency windows, furnaces, water heaters, lighting, Energy Star® appliances, etc.
Achieving the status Step 5, under the BC Energy Step Code for Part 9 homes, indicates the home has been constructed as net-zero energy ready (NZER), and it produces as much energy as it consumes. Local municipal governments can choose if they will require or incentivize a given step for new home construction in their community. The British Columbia government is committed to a target of all new homes being net zero energy ready by 2032.
In this article, we will provide an introduction to net zero principles and how sustainable home design plays a pivotal role in mitigating climate change impacts in the pursuit of sustainability.
The urgency of sustainable design in BC
200 organizations under the B.C. Climate Emergency Campaign have been critical of British Columbia’s CleanBC plan, a provincial roadmap for reducing emissions by 40% by 2030, with a commitment to reach net-zero carbon pollution by 2050. More than 500 members sent a letter to provincial leaders in September of 2021, demanding meaningful change to protect BC from wildfires, flooding and other emergencies that have been attributed to climate change.
According to Grand Chief Stewart Phillip, president of the Union of BC Indian Chiefs, “The Province must fully accept that they need to come up with an alternative economy because we aren’t going to achieve a clean BC with dirty fossil fuels.”
Sustainable design emerges as a key component in achieving these targets, and BC leaders are addressing the environmental impact of the built environment. The province has set ambitious climate action goals that aim to achieve a significant reduction in greenhouse gas emissions.
BC climate action targets
The government of British Columbia has enacted climate action legislation that outlines B.C.’s approach to reducing emissions and transitioning to a low-carbon economy. The province has legislated targets for reducing greenhouse gas emissions by 40% – below 2007 levels – by 2030, 60% by 2040, and 80% by 2050, with an interim target to reduce emissions by 16% by 2025. These targets are legislated under the Climate Change Accountability Act.
In addition to the greenhouse gas emissions targets, BC has introduced measures to reduce methane emissions in the oil and gas sector by 75%. The CleanBC Plan includes a range of energy efficiency actions, to support the transition to clean energy, with investment into a sustainable infrastructure. An energy cap for natural gas utilities has been proposed and is in the works.
The role of sustainable design
Sustainable design involves integrating environmentally responsible practices into every phase of your building’s lifecycle. This includes site selection, material choices, energy use, water conservation, and waste management. Net zero homes not only minimize their carbon footprint but actively contribute to generating clean energy.
A net zero home can significantly reduce or even eliminate your energy bills to provide considerable financial relief. It can offer you energy independence and security because homes with a renewable energy source are less vulnerable to fluctuations in energy prices and potential power outages. With a sealed building envelope, superior insulation, energy-efficient windows and doors, and mechanical ventilation, a net zero home is designed to provide greater comfort and a healthier living environment for your family.
Net zero buildings
Understanding net zero energy
Achieving a balance between the energy your home consumes and the energy your renewable energy source produces requires a holistic approach that prioritizes energy efficiency, renewable energy generation, and smart building technologies. In BC, net zero homes are seen as a key solution for addressing the environmental impact of construction.
The three pillars of net zero
Energy efficiency: Being energy efficient is all about reducing your home’s consumption and demand for energy. It includes the selection of building materials, sealing the building envelope, applying thick continuous insulation, choosing energy-efficient HVAC (heating, ventilation, and air conditioning) systems and implementing smart design strategies that minimize energy wastage.
Renewable energy generation: Solar panels, wind turbines, or geothermal systems are renewable energy options that can generate your electricity onsite. Producing your power not only reduces your family’s reliance on the power grid but also feeds surplus energy back to the grid when your home produces more than it consumes.
Smart technologies: Smart thermostats, automated lighting, smart appliances and energy management software enable your home to adapt to the occupancy patterns of your household and environmental conditions. Sensors, timers, real-time monitoring, data analysis, automation and smart home devices can optimize your energy usage, which can represent significant savings. Smart water leak and freeze detectors can notify you to prevent costly repairs.
Sustainable design principles for net zero energy buildings
Passive design strategies: Cross ventilation makes use of orientation to take advantage of differences in air pressure. Air enters through openings like windows and skylights, flows unobstructed through the interior space, and then exits through openings on the other side of the house. Solar orientation is another fundamental principle for sustainable building, in which the home is strategically placed to maximize sun exposure, providing protection from prevailing winds, and taking advantage of the building site’s natural features. Thermal mass, the ability of a material to absorb, store, and release heat, also contributes to the home’s energy efficiency.
Airtight building envelope: The building envelope, which consists of walls, roof, windows and doors, acts as the barrier between your home’s interior and exterior environments. A well-sealed building envelope prevents air leakage and the loss of heating and cooling energy. By minimizing air infiltration and heat loss, an airtight building envelope will not only save you money but reduce the strain on your heating and cooling systems.
Renewable energy integration: To help achieve net zero energy status, buildings must incorporate one or more renewable energy systems, such as photovoltaic (PV) solar panels or wind turbines. BC’s West Coast offers an abundance of both solar and wind energy.
Photovoltaic systems are a clean source of energy; they do not release harmful air or water pollution. It is practical to mount solar panels on most rooftops or building lots, and they are virtually maintenance-free.
The disadvantage is that they generate electricity only when exposed to sunlight. However, that’s not a problem in British Columbia because BC Hydro offers a net metering program. On this program, the electricity your system generates powers your home first, and any excess is sent to the power distribution grid. Your home’s smart meter tracks how much of the electricity BC Hydro has supplied, and how much excess you’ve sent to the grid. Your excess generation is credited to your account on your next bill.
Wind turbines can produce a significant amount of electricity, particularly if you live in an area with strong and consistent winds. Like solar panels, they also deliver clean energy. They require quite a lot of space, however, and that may raise aesthetic concerns in some residential areas. They only generate electricity when there’s sufficient wind, so they’re often paired with a photovoltaic system. Wind turbines have moving parts, so they will require regular maintenance.
Sustainable materials and construction practices: A selection of high-quality sustainable materials is at the heart of net zero energy building design. BC has seen a recent surge in the use of environmentally friendly building materials such as reclaimed wood, recycled steel, and low-impact concrete alternatives. We’re also seeing designers and builders adopting modular construction techniques to reduce waste and enhance the overall sustainability of their building process.
Net Zero, Passive House, Built Green and Green Building Council’s LEED certification programs in Canada differ in their focuses and approaches, but they share some common sustainability goals. Net zero homes are designed to produce as much energy as, or more than, they consume. The design phase is crucial. Architects and designer-build contractors prioritize energy-efficient building design and sustainability from the outset.
Water conservation and management:
Sustainable design extends beyond energy considerations to include water conservation and management. In communities where water scarcity is a growing concern, net zero homes incorporate water-efficient fixtures, rainwater harvesting systems, and grey-water recycling.
As BC plans for a net zero carbon future, new custom homes will be pivotal players in the transformative journey. Sustainable design principles will help custom homes better integrate with the natural environment, serving as models for what sustainable living can be.
How the BC Energy Step Code Works
Carbon-Neutral Homes: Your Guide to Achieving a Low Carbon Footprint
Zero Emissions Buildings – City of Vancouver
NearZero: A research program with generous incentives to accelerate the decarbonization of BC homes
How to Build an Affordable Net Zero Home in BC
Future-Proof Your Home by Getting it Net Zero Ready
Net Zero vs Passive House: What Are the Similarities and Differences?