The advantages of textile materials as building components include low weight, and in the case of textile membranes, the advantages include translucency and architectural possibilities. A common disadvantage, however, is the fire property of textile materials, which highlights the importance of fire safety assessments for building application of such materials. The work presented in this paper was conducted within the European project contex-T, 'Textile Architecture - Textile Structures and Buildings of the Future'. This paper presents the results of reaction-to-fire tests required for European Standard (EN) 13501-1 classification conducted with a number of textile membranes. The classification results are compared for a selection of these membranes with the information gained from a large-scale reference test that was designed within the project. The reference test was based on the International Organization for Standardization (ISO) 9705 room test. It was seen that the reference test could separate the performance of the different types of membranes investigated and the repeatability of duplicate tests performed was acceptable. However, the classification of the materials by test results from the Single Burning Item (SBI) test (EN 13823) and the small flame test (EN ISO 11925-2) did not reflect the performance of the membranes in the large-scale test properly in all aspects important for fire safety. Most significantly, the 'burn-through' and the associated opening of a hole in the polyvinyl chloride/polyester membranes tested ventilated the hot smoke gases out of the reference room that resulted in limited flame spread and heat production. This mechanism is not modelled correctly by the SBI test, which leads to a discrepancy between classification and large-scale behaviour.