Infrared thermographic investigation procedures for four types of generic exterior wall assemblies

Exterior wall assemblies that enclose medium to large buildings can be classified into four generic wall types: 1) masonry 2) architectural precast 3) metal and glass curtain wall 4) insulated steel assemblies. Within these generic types of assemblies there are variations within the cladding type as well as assembly configuration. Investigations of exterior wall assemblies using infrared thermographic radiometers are carried out to obtain information related to: 1) moisture accumulation, 2) air leakage, 3) variations within thermal resistances of similar assembly configuration and 4) structural thermal bridging. Each generic type of wall assembly is designed to perform in a different way and their use in various conditions are governed by their performance specification. The thermal patterns generated by each of these wall types is unique. The tolerances for error on each type of assembly varies. Therefore the inspection methodology for each type of wall assembly needs to be defined to isolate the specific performance parameters relevant to each wail assembly type. This paper identifies the various exterior wall assembly types, discusses the relevant performance parameters that make these assemblies perform properly and defines the inspection requirements necessary for accurate assessment of the deficiencies within the exterior wall enclosures of buildings.