A New Method of Pixel-level In-situ U-value Measurement for Building Envelopes Based on Infrared Thermography
This addresses energy auditors' need for more accurate building envelope assessments to improve energy modeling, though it is incremental as it builds on existing IRT-based methods.
The paper tackled the problem of inaccurate U-value measurements in building energy audits by proposing a pixel-level infrared thermography method that uses 2D spatial temperature distributions, resulting in better reflection of actual thermal insulation performance compared to single-point methods.
The potential energy loss of aging buildings traps building owners in a cycle of underfunding operations and overpaying maintenance costs. Energy auditors intending to generate an energy model of a target building for performance assessment may struggle to obtain accurate results as the spatial distribution of temperatures is not considered when calculating the U-value of the building envelope. This paper proposes a pixel-level method based on infrared thermography (IRT) that considers two-dimensional (2D) spatial temperature distributions of the outdoor and indoor surfaces of the target wall to generate a 2D U-value map of the wall. The result supports that the proposed method can better reflect the actual thermal insulation performance of the target wall compared to the current IRT-based methods that use a single-point room temperature as input.