How to Detect and Observe Hidden Window Leaks Using Infrared Thermography

摘要

Water intrusion through residential window assemblies is one of the leading causes of damage to the interior. The source is frequently the result of failed seals at window frame jamb/sill intersections or incorrectly installed window flashings. To find the source of and pinpoint the cause(s) of this type of leakage can be destructive, time consuming, and results in high investigation and repair costs. Several instruments can be used to detect and trace water intrusion nondestructively; the most popular are conductive or capacitance-type meters. These meters measure the electrical properties of building materials to indicate wet or dry materials. Often, the readings may be falsely interpreted as an indication of elevated moisture levels when metal is present in the region of the readings. Infrared thermography is successfully being used to detect and trace leakage in building envelopes. Its ability to detect and graphically display heat radiated from a target building area enables an operator to quickly detect leakage with very little interpretation. Although this technology is not new, its use for building envelope diagnostics is new; capabilities in this area are still being discovered. We recently conducted an infrared thermography survey to detect water intrusion at interior window sill regions from failed window frame corner assemblies. The investigative team also used a time-lapse survey to visually track the leakage path. We verified the leak with a capacitance-type meter and through visual observation of materials that became wet from the leak. An infrared thermography survey provides another useful method for quickly and efficiently detecting this type of window leakage.