Propuesta metodológica para estimación de la vida útil de la envolvente de los edificios

The estimation of the service life of the construction elements of a building and its materials is an essential part of drawing up a realistic and economically viable maintenance program. In this regard, this paper presents a methodology to estimate the service life of the construction systems of outer walls and roofs frequently used in modern buildings. The reference document used was the ISO-15686 standard, which proposes an efficient method of estimating service life based on durability factors. However this method was designed for general application and is difficult to apply. Due to the scarce amount of reliable information available on material durability values, it was found necessary to generate a service-life database of the construction elements considered, as well as of their component materials, based on their common degradation mechanisms. Factors that affect durability were also identified and a clear procedure for evaluation was set up. The proposed method, rather than giving accurate information on service life, allows different construction systems to be compared and is thus of assistance in the project design phase. The methodology can also be used as a model for other construction elements and is transferable to other countries.La estimación de la vida útil de los elementos constructivos de un edificio y de sus materiales, es fundamental para elaborar programas de mantenimiento realistas y viables económicamente. En este sentido, el presente trabajo presenta una propuesta metodológica para estimar la vida útil de fachadas y cubiertas más frecuentes en edificación. El documento referencia utilizado ha sido la norma ISO-15686, que propone un método eficiente para estimar la vida útil, basándose en los factores que afectan a la durabilidad, pero que sin embargo está planteado de forma muy generalista de difícil aplicación. Constatada la escasa información fiable sobre durabilidades de los materiales, ha sido necesario generar una base de datos de vida útil de los elementos constructivos considerados, así como de sus materiales componentes, a partir de los mecanismos de degradación que con más frecuencia pueden afectarles. Asimismo se han identificado factores que afectan a la durabilidad y se ha propuesto un procedimiento claro para su evaluación. El método planteado, más que dar una información precisa sobre la vida útil, permite comparar diferentes sistemas constructivos y facilita al técnico su diseño en fase de proyecto. La metodología puede servir de modelo para otros elementos constructivos o para otros países.Ortega Madrigal, L.; Serrano Lanzarote, AB.; Fran Bretones, JM. (2015). Proposed method of estimating the service life of building envelopes. Revista de la Construcción. 14(1):60-68. doi:10.4067/S0718-915X2015000100008S606814

Thermal behavior analysis of different multilayer façade: Numerical model versus experimental prototype

[EN] In this paper, different sorts of façades have been analyzed considering their thermal performance along a 24 h period. A numerical model was developed and compared with experimental measurements considering two different façades for buildings: on one side an opaque multilayer façade; and on the other side, a ventilated façade. The numerical model representing the temperature in every layer of the façades was successfully validated. This model was used for determining the thermal behavior of two new ventilated façades in which the thermal mass had been changed, observing then that the existence of the movements in the air gap affected particularly the air temperature and the thermal transmittance of the façade while the sun hitting the façade, leading to a reduction of transmittance close to 30% along the air chamber. This effect is very important in warm climates and becomes a key-factor for decreasing the cooling needs of buildings in summer with no need of increasing the mass of the façadeThe evaluation of the different facade systems, by modifying multilayer sandwich panels was performed in the framework of the E3 EDIFICACION ECO EFICIENTE project. The research project was cofounded by CDTI and a consortium of companies formed by BECSA, CERACASA, Rockwool Peninsular, ATERSA and APLICAD.Guillén Guillamón, IE.; Gómez Lozano, V.; Fran Bretones, JM.; López Jiménez, PA. (2014). Thermal behavior analysis of different multilayer façade: Numerical model versus experimental prototype. Energy and Buildings. 79:184-190. https://doi.org/10.1016/j.enbuild.2014.05.006S1841907