Performance-based methodology for the fire safe design of insulation materials in energy efficient buildings
Hidalgo-Medina, Juan P.
This thesis presents a methodology to determine failure criteria of building insulation materials in the event of a fire that is specific to each typology of insulation material used. This methodology is based on material characterisation and assessment of fire performance of the most common insulation materials used in construction. Current methodologies give a single failure criterion independent of the nature of the material – this can lead to uneven requirements when addressing materials of different characteristics. At present, fire safety codes establish that performance of different materials or assemblies is assumed to be “equivalent” when subject to the same test, where attainment of the unique failure criteria occurs after a required minimum time. Nevertheless, when using extremely different materials this may not be actually the case. Building performance is currently defined in a quantitative way with respect to factors such as energy usage (i.e. global thermal transmittance), element weight (i.e. thickness and mass), space utilisation and cost of application. In the case of fire performance, only a threshold value is required, therefore a quantitative performance assessment is not conducted. As a result, the drivers are those associated with the variables that can be quantified, whereas the thresholds merely need to be met without any alternative for a better performance. This work opens the door to a performance-based-design methodology that takes into account fire performance as an optimisation variable for the building design, to be used with all other quantifiable variables. An added advantage is that the numerical tool required embraces a low level of complexity. As a result, the possibility for any insulation product to achieve quantifiable and acceptable fire safety levels for required energy efficiency targets is established. As a final remark, an application of the performance assessment methodology that introduces fire safety as a quantifiable variable is presented.