This work presents a photogrammetric technique that provides geometric and thermal information about building façades. It uses low cost and portable scale bars, specially designed for thermal imaging, and processing software based on single image rectification. Image rectification corrects the original photo displacement due to the projection and perspective, and radial distortions introduced by the lens of the camera. The technique is tested by comparing laser scanning and thermal data. Seven segments of different orientation and length are selected for the measurement. Accuracy tests show errors between 44mm and 151mm. Precision values range between 22mm and 61mm for a maximum length of 7259mm. The accuracy and precision results obtained for the technique open the possibility of extending its use to building inspection tasks.