b"INFRARED THERMOGRAPHYEXPANDING THE ROLE OF INFRARED THERMOGRAPHY IN ENERGY RETROFITTINGOF BUILDING ENVELOPESBy Phalguni Mukhopadhyaya 1, *, PhD, FCSE, FCAE, and Milad Mahmoodzadeh, PhDINTRODUCTION INFRARED THERMOGRAPHY: Buildings are one of the largestA NON-INVASIVE AND consumers of energy and producersCOMPREHENSIVE APPROACHof carbon emissions, especially in coldInfrared Thermography (IRT) offers a climates like Canada, where buildingspowerful alternative to traditional energy account for up to 40 per cent of the totalaudit methods. By capturing the infrared energy demand. As urban areas continueradiation emitted by building surfaces to grow, with buildings accounting for(Figure 1), IRT allows for identifying up to 60 per cent of energy consumptiontemperature variations that indicate in these regions, the need for effec- potential thermal anomalies, such as tive energy efficiency measures is moreair leakage, moisture accumulation and pressing than ever. Retrofitting existingthermal bridges. By identifying theseFIGURE 1INFRARED IMAGE CAPTURES buildings to improve their energyTEMPERATURE VARIATIONS THAT INDICATE performance is a key strategy in reducingissues, IRT enables more targeted andTHERMAL ANOMALIES.overall energy demand and carboneffective retrofit strategies, ensuring that emissions. However, the success of theseinterventions address the root causes ofbuilding's thermal performance, repre-retrofits largely depends on the reliabilityenergy loss rather than just the symp- senting the rate of heat transfer through of the initial energy audit of exteriortoms. Unlike traditional methods, IRT isa building component. Accurately building envelopes, which identifies thenon-invasive and can be performed bothestimating the U-value is essential for areas most in need of improvement.internally and externally, providing adetermining the effectiveness of insula-Traditional energy audit methods, suchcomprehensive assessment of a building'stion and other energy-saving measures.as nominal U-value calculations, heatthermal performance without disruptingThe researchers compared IRT-estimated flux meters (HFM) and simulation tools,its operations or occupants. U-values with those obtained from the are often inadequate. These methods canADVANCING IRTsimulation tool, revealing significant be invasive, expensive, time-consumingMETHODOLOGIES: deviations, particularly in well-insulated and fail to account for real-world condi- walls. These deviations were attributed to tions like thermal bridges, air leaks andA FOCUS ON factors such as vignetting (colder corners moisture content in building materials.U-VALUE ESTIMATION in thermal images) and environmental As a result, they may not accuratelyThe research conducted at the Universityconditions during the tests. To address and efficiently reflect the true thermalof Victoria goes beyond traditional IRTthese challenges, the researchers intro-performance of building envelopes,applications by developing and validatingduced a practical approach that involves leading to suboptimal retrofit strategies.quantitative methodologies for esti- taking thermal images from multiple An ongoing research initiative at themating the U-value of wall assemblies.angles and stitching them together University of Victoria (B.C., Canada) hasThe U-value is a critical indicator of ato improve accuracy (Figure 2). This been exploring the innovative application of quantitative Infrared Thermography (IRT) for this purpose, offering a non-invasive and rapid approach to energy audits of exterior building envelopes.1 Professor, Department of Civil Engineering,University of Victoria, BC, Canada2Building Energy Consultant at Morrison Hershfield Now Stantec; Adjunct Professor at University of Victoria, BC, Canada* FIGURE 2TAKING INFRARED IMAGES FROM MULTIPLE ANGLES AND STITCHING THEM Corresponding author, phalguni@uvic.ca TOGETHER ALLOWS FOR A MORE RELIABLE ESTIMATION OF U-VALUES.14 BCBEC ELEMENTSA BCBEC PUBLICATION"