Fog, Fans and Forward-Thinking in Charlotte
In Mattamy’s Charlotte Division, Matthew Byington, Sustainability Manager for Charlotte and Raleigh, led an eye-opening test to track and address air leakage – an invisible issue that can significantly reduce energy efficiency and home comfort.
To run his experiment, Byington borrowed a page from the theatre world, combining a blower door with a fog machine to make the airflow inside the home visible. The method proved to be a powerful diagnostic tool.
“Traditionally, blower doors are used to measure overall air leakage in a home,” said Byington. “But we wanted to go a step further to see exactly where that air was escaping. By adding fog, we got a clear picture of how our building envelope performs in real-world conditions.”
In one scenario, the team depressurized the home using the blower door and released fog into the attic. As the home pulled air inward, fog travelled through tiny gaps in the second-floor ceiling – an area without a secondary air barrier.
Seeing these entry points in action helped the team better understand where improvements such as caulking or sealing could have the biggest impact.
In another test, the fog machine was placed near the HVAC return vents while the supply vents were sealed. This setup revealed leaks in the ductwork located in the attic, which – although outside the insulated space – still forms part of the home’s conditioned envelope. Identifying such trouble spots helps the team improve HVAC system efficiency and ensure future homeowners enjoy more comfortable, cost-effective living spaces.
Byington’s next steps are to perform the same tests at various stages of construction to help identify and prevent leaks that may be covered by drywall or insulation. “We want to fine-tune our testing methodology so we can quantify our results before recommending that other divisions perform this widely.”
With a little fog and a lot of forward thinking, the Charlotte team’s testing method could serve as a model for future air-sealing improvements.
To run his experiment, Byington borrowed a page from the theatre world, combining a blower door with a fog machine to make the airflow inside the home visible. The method proved to be a powerful diagnostic tool.
“Traditionally, blower doors are used to measure overall air leakage in a home,” said Byington. “But we wanted to go a step further to see exactly where that air was escaping. By adding fog, we got a clear picture of how our building envelope performs in real-world conditions.”
In one scenario, the team depressurized the home using the blower door and released fog into the attic. As the home pulled air inward, fog travelled through tiny gaps in the second-floor ceiling – an area without a secondary air barrier.
Seeing these entry points in action helped the team better understand where improvements such as caulking or sealing could have the biggest impact.
In another test, the fog machine was placed near the HVAC return vents while the supply vents were sealed. This setup revealed leaks in the ductwork located in the attic, which – although outside the insulated space – still forms part of the home’s conditioned envelope. Identifying such trouble spots helps the team improve HVAC system efficiency and ensure future homeowners enjoy more comfortable, cost-effective living spaces.
Byington’s next steps are to perform the same tests at various stages of construction to help identify and prevent leaks that may be covered by drywall or insulation. “We want to fine-tune our testing methodology so we can quantify our results before recommending that other divisions perform this widely.”
With a little fog and a lot of forward thinking, the Charlotte team’s testing method could serve as a model for future air-sealing improvements.