Since the discovery of Portland cement in the 19th century, it has become the most widely used binder in construction. However, its use in the conservation of Cultural Heritage (CH) buildings has raised concerns over its incompatibility with historic bricks and lime-based mortars. This study explores the potential of Multispectral Imaging (MSI) as a non-destructive technique for differentiating between cement- and lime-based mortars. By analyzing mortar reflectance in the Short Wave Infrared (SWIR) spectral range, we demonstrate that SWIR yields significantly more accurate material classification than standard visual Red Green Blue (RGB) imaging. We achieved 100% overall classification accuracy in distinguishing between cement and lime mortars, with 99% accuracy obtained solely from the shape of the SWIR signatures rather than their total intensity. Additionally, when integrated with drone systems, MSI technology greatly enhances the inspection efficiency of building facades, particularly in hard-to-reach areas, making it an ideal solution for automating pre-restoration assessments.