THERMAL ENVELOPE DIAGNOSTIC TECHNIQUES
Diagnostic techniques have been developed to investigate the thermal performance of building envelopes as
installed. These techniques have served to identify many of the performance problems referred to in these
guidelines and also provide practical tools for investigating their existence in any given building through a
program of envelope testing during the construction phase of a project. This section discusses the diagnostic
techniques along with measurement standards and performance ratings relevant to each. Detailed
descriptions of these diagnostic techniques are provided in the listed standards and references. More general
descriptions, along with example test results are contained in Persily [1986 and 1988] and Grot .
As discussed below, some of these techniques can be applied to a mock-up of the thermal envelope prior to
construction in order to assess the thermal performance of the design when the opportunity still exists to
modify the design. Other techniques are applicable to the completed building envelope to assess the as-built
performance. These diagnostic techniques are not generally employed in all building projects, though they
are more common in larger projects. The American Architectural Manufacturers Association (AAMA)
suggests the use of diagnostic testing on curtain walls and has developed useful documents describing the
test methods and guide specifications for their use.
The diagnostic techniques presented in this section are organized into the following areas: