Improving the thermal performance of the existing building stock is essential to significantly reduce the overall energy consumption in the building sector. A key objective is the retrofitting of the existing building envelope. A necessary first step in the building envelope optimization process is the assessment of its actual thermal performance. This assessment should be repeated after retrofitting to clearly define the improvements that were made and the heat loss reduction that was achieved. In this study, an efficient, non-destructive, in-situ measurement method, based on an outdoor infrared thermographic survey, is developed to determine the thermal bridging performance. As wind velocity significantly influences the heat losses through the building envelope, this study includes quantification of the wind velocity impact on the Ψ-value. This was assessed by undertaking ITT of the same thermal bridge at various wind velocities, in a controlled environment, in a hot box device. The results showed that the Ψ-value is highly dependent on wind velocity so that measurement of the Ψ-value taken at different wind conditions cannot be directly compared. An adjustment procedure is proposed that can be used to convert the Ψ-value measured at any wind velocity to a standard value corresponding to a velocity of 4 m/s. From a practical point of view, this adjustment procedure makes the methodology widely applicable.

改善现有建筑材料的热力性能对于显着减少建筑行业的整体能耗至关重要。一个主要目标是对现有建筑围护结构进行改造。建筑围护结构优化过程的必要第一步是评估其实际热性能。改装后应重复进行此评估，以明确定义已进行的改进和已实现的热量减少。在这项研究中，开发了一种基于室外红外热像仪测量的有效，无损的原位测量方法来确定热桥性能。由于风速会显着影响通过建筑物围护结构的热量散失，因此本研究包括对风速对建筑物的影响进行量化。Ψ值。通过在可控环境中，在热箱设备中以各种风速对同一热桥进行ITT评估来评估这一点。结果表明，在Ψ -值是高度依赖于风速，因此那测量Ψ在不同风力条件下采取-VALUE不能直接进行比较。提出了一种调整程序，该程序可用于将在任何风速下测得的Ψ值转换为对应于4 m / s速度的标准值。从实际的角度来看，这种调整程序使该方法广泛适用。