This document covers all life cycle stages, from cradle to grave, namely product stage, construction process stage, use stage and end-of-life stage of glass products (see Clause 4), used in buildings. While covering all life cycle stages, this PCR primarily focuses on the product stage, in particular the manufacturing of flat glass and the consequent processing into flat glass products (as listed in point 4.), from cradle to gate. It covers raw materials and energy supply, transport, flat glass manufacturing, flat glass processing, packaging and storage. All requirements and recommendations in this PCR for the elaboration of the Life Cycle Inventory may be applicable to flat glass used in other applications. This PCR includes the rules to produce EPD that contains more than one thickness or configuration of the same product.