Glass sensors, based on K-Ca-silicate glass chips, with a low durability against corrosive stresses, offer a new method for assessing the complex environmental stress situation of monuments and pieces of art. The easy-to-handle technique is able to detect the combined impact of climatic stresses, pollution and microbiological effects as well as synergetic interactions. The chemical composition of the sensitive glasses enables judgements within few months. This way long-term estimates can be obtained without costly long-term investigations. The corrosion progress is determined by microscopy and IR-spectroscopy of the weathered glass sensor surfaces. The sensors are already operating in the field of stained glass window preservation. They monitor the efficiency of different kinds of external protective glazings and the remaining stresses from the in-door environment of cathedrals.