This document gives guidance on the process and development of extended fields of application using test results obtained from CEN/TS1187, tests1 to 4, and included in test reports, and other relevant information in order to evaluate and classify the performance of roofs/roof coverings. This document provides a methodology to consider the possible effect(s) on classification to EN13501?5 from single or multiple changes to the individual product and end-use application parameters of the roof/roof covering.Specific application guidance is given in AnnexA, AnnexB, AnnexC and AnnexD for CEN/TS1187, tests1 to 4 respectively.