What thermographic pattern typically indicates air leakage in a building envelope during winter inspections?

What thermographic pattern typically indicates air leakage in a building envelope during winter inspections?

What thermographic pattern typically indicates air leakage in a building envelope during winter inspections? A) Diffuse warm areas     B) Linear cold streaks along framing     C) Uniform heat distribution     D)Circular hot spots Answer: Linear cold streaks along framing During winter inspections, the inside of a building is warm while the outside is cold. When air leakage occurs, cold outside air infiltrates through: Gaps in insulation Cracks in walls Poorly sealed joints Stud cavities and framing interfaces What happens thermally? The infiltrating cold air cools the surface locally This cooling often follows structural paths like studs, joists, or framing On a thermal image, this appears as linear (line-shaped) cold patterns Key characteristics: Straight or slightly irregular lines Often aligned with wall studs or framing members Cooler than surrounding areas More visible when there is a good temperature difference (ΔT) Thermography Principle Behind It Air leakage is a form of convective heat transfer, …