A Building Envelope Characterization Workflow for In-Situ Thermal Performance Assessment

As buildings age, retrofits are becoming an increasinglyimportant topic for the ever-growing and aging existingbuilding stock. With 50% of American buildings builtbefore 1980 and only 0.5–1% of existing buildingsretrofitted annually, thermography can be used to nonintrusivelycharacterize building envelopes to informenergy modeling, façade design, and project appraisalfor potential projects. This paper presents a short reviewof literature and published methods to characterizeexisting building envelopes' thermal properties, followedby a preliminary thermography-based methodology tocharacterize the thermal resistance and thermal massproperties of a building envelope. The proposedmethodology utilizes optimization-enabled transientfinite elements to characterize envelope thermalproperties. The verification of this methodologyshowcased that the proposed finite-element workflowcan adequately characterize an envelope’s thermalperformance. This methodology serves as a foundationfor future research in building envelope defectcharacterization.