The Role of Airtightness on Hamilton’s Path to Net-Zero by 2050
Green Venture’s energy team had the opportunity to attend the 5th annual Canada’s Innovation Corridor Summit, a leadership gathering focused on driving regional collaboration between Toronto, Kitchener-Waterloo, and Hamilton in business, government, and the associations’ sector. This year’s theme was Transition to Net-Zero, which focused on the opportunities and challenges within the context of decarbonization. More specifically, the conference discussed topics related to our progress in industry, research, transportation, and infrastructure.
In a breakout room presented by Building Knowledge Canada and Nerva Energy, we explored the role of airtightness in our buildings. As homeowners, we understand that we spend a significant amount of time at home, heating and cooling our spaces to keep ourselves comfortable. The problem we see within older homes is that they are inherently energy inefficient. This can be attributed to outdated building practices or, often enough, careless or shoddy construction work.
Energy leakage in a home can result in outside air entering and/or leaving the building. Meaning, the air we pay to heat and cool our home finds its way out through cracks in the building envelope. As a result a home’s poor airtightness may lead to the following:
- Flawed energy efficiency
- Increases in energy usage
- Higher space heating and cooling costs
- Thermal comfort issues
- Increased dependence on fossil fuels (increasing greenhouse gas emissions)
In the building industry today, common practice for airtight sealing is a result of manual labour. Contractors are hired to visually identify and manually seal leaks individually using caulking and sealants. Oftentimes however, holes and spaces that are unable to be seen with the human eye can be missed, which means the building may not become as airtight as possible. An exciting technological solution that could help maximize the air tightness of our buildings on the path to net-zero is aerosolized caulking technology.
AeroBarrier is an atomized insulation that helps seal gaps through a self guided process. The process begins during the construction phase of a home or during a deep energy retrofit. The first step is to place nozzle stations in all rooms requiring air sealing. All large openings and crevices that are not meant to be sealed are then shut and taped closed. Next, the building is pressurized like a balloon, and as the air passes out through the cracks of the home so too does this atomized insulation which is dispersed via the nozzle stations. The aerosolized caulking finds its way through the gaps and collects on the crevices as it reacts to the exterior environment. The caulking builds on it
self, eventually sealing all gaps within the building.
AeroSeal, a counterpart to AeroBarrier, aims to seal air ducts instead of the whole building envelope. Unlike AeroBarrier, AeroSeal can be implemented during building occupation in a fully constructed home with little to no disruption. The forced-air system in a home is sealed and pressurized just as the AeroBarrier system is. From here the aerosolized caulking is dispersed and finds its way through any gaps, building on itself to seal the duct system tightly. This technology could be more favorable for existing buildings as there is no need to gut the walls of insulation and drywall. Sealing your duct system can lead to benefits such as:
- Eliminating energy leakage (lowering monthly bills by ~10-20% or more depending on the home)
- Lowering greenhouse gas emissions
- Reducing the frequency of HVAC system operations
- Increasing comfort levels and indoor air quality
These technologies presented at the Summit are a means to optimize air-sealing to fasttrack our decarbonization journey. It is important to remember however that DIY air sealing or hiring a contractor to seal windows, doors, and any gaps within the building envelope is still very much worth the effort. Moving forward, we expect to see improvements in technology such as these, but as of right now, we challenge homeowners to target the low-hanging fruit during their home retrofits. Please reach out to our energy team for more information or to book your home energy evaluation with us to discover how airtight your home is and to take advantage of available grants, rebates and interest-free loans!