The visual impact of architectural glass facades is significantly influenced by the colour perception of coated glass. While glass selection is primarily driven by performance factors such as solar control and thermal properties, aesthetic attributes such as colour are also critical in architectural design. Despite their significance, these aspects remain largely subjective, leading to variations in perceived colour depending on the observer and the lighting conditions under which the glass is evaluated. Factors such as daylight variations and viewing angles further complicate colour assessment, making it difficult to accurately predict the true appearance of coated glass. Conventional selection methods rely on visual inspection and qualitative descriptions, which lack precision and may introduce misleading expectations for architects and designers. This study presents a systematic approach to coated glass selection through colorimetry analysis based on the CIE Lab* colour space, a standardized model for quantifying colour perception. By analysing both reflected and transmitted light properties, this method provides an objective framework for assessing glass colour. The integration of spectral data into the selection process enhances accuracy in colour quantification, enabling architects and designers to make informed, data-driven decisions in architectural glass facade design. The application of colorimetry streamlines the glass selection process by minimizing the impact of perceptual discrepancies and ensuring consistency in the assessment of coated glass. This study emphasises the importance of transitioning from subjective evaluation methods to a physics-based approach for achieving more precise and reliable evaluations of coated glass colour.