Case Studies

Summary & Key Findings

4 Elements Integrated Design conducted 5 energy efficiency evaluations of existing homes throughout Calgary. The homes spanned a range of sizes, age and level of energy efficiency. Each home was scanned with a professional high definition infrared (IR) thermal imaging camera before and after completing a blower door test, under which the home was depressurised with a calibrated fan and air flows measured. As a blower door test simulates the effects of a windy day on the home, air leakage areas are enhanced for visual identification, as well as measuring the total air leakage.

In each home, a detailed Heat Loss Map showing the IR pattern of the roof was reviewed while on-site. Several consistent findings were noted in using this image while completing the evaluations of the homes:

1. In all cases, investigation revealed potential thermal and air tightness issues that correlated to warm areas in Heat Loss Maps. Poorly sealed attic hatches, plumbing stacks and poorly sealed mechanical chases all appear to match locations on the MyHEAT image.
2. On the least energy efficient homes, the Heat Loss Map provided the most relevant information. More areas were identified that also correlated to Heat Loss Maps in more efficient homes.
3. The outline of the heated footprint was noted as including unheated spaces such as garage and covered entries while missing heated spaces such as sun rooms.
4. Homes with the original attic insulation were more likely to have no other improvements or upgrades. Since attic insulation is one of the simplest and least costly upgrades, it is often completed before other improvements such as windows, or furnaces.

Note: Heat Loss Maps show red as hot, and blue as cold. The handheld IR images show white and yellow as hot, and purple and blue as cold.

Conclusion

In the individual case studies for each home, MyHEAT’s Heat Loss Maps provided helpful information. They showed a vantage point not available from the ground for thermography and contributed a “bird’s eye-view” to assist in the review of the home energy efficiency. This adds important value for Thermographers and Energy Advisors in providing an accurate energy efficiency evaluation (as possible) to the homeowner.

Through the energy efficiency evaluations of these homes, a wide range of performance was assessed. The Heat Loss Maps supported and reinforced findings based on the blower door testing, thermography and the energy advisor’s own knowledge of construction over various ages of homes. Even the most efficient home of the sample benefited from the review in finding construction weaknesses that were allowing higher than acceptable humidity to accumulate in the attic. Clearly the older, least upgraded homes have the most opportunity for energy savings. As attic insulation is typically one of the first upgrades made on older homes, an understanding of the attic insulation provides a key indicator of the overall efficiency of the home. In the least upgraded homes, there was stronger relationship between the findings of the evaluation and major indicators from Heat Loss Maps.