Weatherization: A crucial tool for achieving net zero 

Optimizing energy efficiency in buildings is incredibly important for reducing overall energy consumption, GHG emissions and spikes in peak demand. Whether the upgrades are quick and easy or part of a deeper retrofit, starting with simple energy efficiency measures not only has the potential to create a big impact towards net zero, it will also likely save you a decent chunk of change on your heating bill!

The world wastes more energy than it uses every year. Every year, month, day, hour and minute we waste more energy than we consume. With such a large amount of waste, it’s no surprise that energy efficiency is the cheapest and most environmentally sound way to meet our world’s growing energy requirements. Fossil fuels burned to produce energy for buildings contribute more than 10% of U.S. energy-related greenhouse gas (GHG) emissions.  

This makes building weatherization pivotal in the global stride towards net zero emissions, particularly in the context of weather-driven peak load events. Peak load energy, which occurs during extreme weather events like heat waves or cold snaps, necessitates substantial energy generation capacity that remains underused most of the year. Building and maintaining this excess capacity is costly because utilities must invest in infrastructure that can handle these high peaks, despite their infrequent occurrence. This leads to increased energy costs for both utilities and homeowners.  

“Weatherization alone offers a straightforward and economical way to reduce emissions and energy costs, making it an indispensable first step towards achieving a resilient, comfortable, and energy-efficient home in the face of peak demand challenges.”

Darren Jones

Key Benefits of Weatherization

Weatherization is the process of protecting a building’s interior from outside elements like precipitation, cold air in winter months, and hot, humid air in summer months.  Improvements to the building’s envelope – such as air sealing, insulation, and replacing older windows and doors – acts directly to lower the overall energy requirements of homes, which is critical during periods of energy demand spikes. By improving the energy efficiency of buildings, weatherization helps to stabilize the energy grid and provide more reliable power to consumers. This is crucial in regions already facing the extremes of climate change, with unexpected and severe weather events becoming more common. 

A recent study highlights the significant impact of residential weatherization on reducing energy use, peak loads, and GHG emissions. Let’s examine the various weatherization efforts that homeowners can undertake, ranked by the level of effort and investment required for each. 

Categorizing Weatherization Efforts

Easy Upgrades (Potential Energy Savings: 12%-18%)

• Weather stripping and caulking: These are some of the quickest and most cost-effective weatherization measures. Sealing leaks around doors, windows, and other openings can be done for as little as $50 to $100. Such efforts provide substantial returns on investment by preventing air leaks. 
   
• Attic insulation: This is another level of weatherization that can be either a DIY project or professionally handled. It typically costs between $500 and $2,000 in Canada, depending on the approach and scale of the project. 

Deeper Retrofits (Potential Energy Savings: 11%-14%)

• Window replacements and wall insulation: These are the most intensive projects, often requiring professional help and potentially building modifications. Costs can vary widely, from $10,000 to $50,000. Homeowners are advised to conduct a home energy assessment to fully understand the costs and benefits, which extend beyond energy savings to improved home resilience and comfort. 

In addition to energy savings and improved grid reliability, weatherization enhances homeowner comfort and resilience during extreme weather. 

Going Beyond Weatherization: Efficient heating and cooling

After addressing air sealing and insulation, homeowners can consider more efficient methods to heat and cool their spaces. Options like air-source or ground source heat pumps can significantly reduce the energy needed to heat and cool a home compared to older systems. Switching homes and buildings to using heat pumps is a strategy known as electrification. 

Heat pumps, contrary to their name, can tackle both heating and cooling. They use electricity very efficiently, converting 1 unit of electricity into 3 units of thermal energy for heating or cooling a space. This is known as the Coefficient of Performance (COP). Natural gas heating on the other hand has a COP of 0.9, meaning every 1 unit of gas is converted into 0.9 units of thermal energy.  

Air source heat pumps are a more common option than ground source heat pumps, as they allow for a more cost-effective installation, with the average cost at $10,000 – $20,000. Air source heat pumps typically have a payback period around 5-10 years, depending greatly on climate, energy costs and local incentives or rebates. 

Geothermal or ground source heat pumps have higher capital costs ($15,000-$40,000+) and have feasibility limitations for homeowners without a yard available. However, for regions with very cold winters, a ground-source heat pump system can yield savings of about 10-20% more than an air-source heat pump. Because underground temperatures are warmer during winter, compared to air temperatures, a ground source heat pump system can deliver heat more efficiently throughout the winter season. The payback period on a ground-source heat pump can be between 5-10 years, although this can vary significantly depending on a variety of factors described above. 

Start with Weatherization

Before upgrading to more efficient heating and cooling systems, the foundational step of weatherization not only lowers initial costs, but also maximizes the efficiency of any subsequent heating or cooling upgrades. By first making moderate weatherization improvements to the home, right-sizing can reduce the lifetime cost of owning and operating a heat pump by $3,000 to $11,000.  

Weatherization alone offers a straightforward and economical way to reduce emissions and energy costs, making it an indispensable first step towards achieving a resilient, comfortable, and energy-efficient home in the face of peak demand challenges. 

There is an opportunity and role for all levels of governments to play in accelerating building weatherization. Incentives and rebates which can reduce the total cost of installing and operating a heat pump can drastically increase the rate of heat pump adoption. In addition, community-led bulk purchasing or a pooled procurement of weatherization or electrification hardware and services can demystify the process, reduce costs for all participants, and increase adoption of these efforts by word-of-mouth.  

Weatherize your home today to take a significant step towards sustainability and energy savings!