Demanda de calefacción y refrigeración en edificios: Comparación entre un modelo paramétrico y un edificio auditado.

Urban population growth together with energy demand increase, among other consequences, provokes the augment of greenhouse gasses emissions (GGE), which contribute to Climate Change. Energy efficiency in buildings becomes essential to reduce demand, keeping acceptable comfort levels for users. Office, housing and commercial buildings consume more than one third of the primary energy produced in Argentina, a similar percentage worldwide. New digital technologies to afford this complex problem combine architectural design and building energy modelling (BEM), like parametric architecture. This tool enables complex tasks as energy efficient building design where materials, energy and information must be considered simultaneously. All these variables can be gathered into one unique transparent process, putting forward energy demand as a key factor for conceptual design decisions. In this paper, we compare the heating demand for one typical winter day with the demand of a house audited by our Laboratory, in order to calibrate our model. The audit shows the results before and after energy efficiency refurbishment. We also calculate the cooling demand for one typical summer day for a future comparison with the audited building.El crecimiento de la población urbana con el aumento de la demanda energética, entre otras consecuencias, provoca la suba de las emisiones de gases de efecto invernadero (GEI) que contribuyen al Cambio Climático. La eficiencia energética en los edificios es imprescindible para reducir dicha demanda manteniendo niveles de confort aceptables para el usuario. Los edificios destinados a uso residencial, comercial y administrativo consumen más de un tercio de la energía primaria producida en Argentina, porcentaje similar al resto del mundo. Las nuevas tecnologías digitales para solucionar este problema combinan la proyectación arquitectónica con la simulación de la performance energética, entre ellas, el diseño paramétrico. Este se ha transformado en una valiosa herramienta para encarar tareas complejas como ser el diseño de edificios eficientes, donde se requiere considerar materiales, energía e información. Este procedimiento permite reunir todas estas variables en un único proceso transparente, haciendo de la demanda energética una cuestión determinante en las decisiones proyectuales tempranas. En este trabajo se comparan la demanda en calefacción de un día típico de invierno con la demanda obtenida a partir de una vivienda energéticamente rehabilitada auditada por nuestro Laboratorio, a fin de calibrar el nuevo modelo. Asimismo se calcula la demanda de refrigeración para su posterior comparación con el edificio auditado

Methodological Approach for the Development of a Simplified Residential Building Energy Estimation in Temperate Climate

Energy ratings and minimum requirements for thermal envelopes and heating and air conditioning systems emerged as tools to minimize energy consumption and greenhouse gas emissions, improve energy e ciency and promote greater transparency with regard to energy use in buildings. In Latin America, not all countries have building energy e ciency regulations, many of them are voluntary and more than 80% of the existing initiatives are simplified methods and are centered in energy demand analysis and the compliance of admissible values for di erent indicators. However, the application of these tools, even when simplified, is reduced. The main objective is the development of a simplified calculation method for the estimation of the energy consumption of multifamily housing buildings. To do this, an energy model was created based on the real use and occupation of a reference building, its thermal envelope and its thermal system’s performance. This model was simulated for 42 locations, characterized by their climatic conditions, whilst also considering the thermal transmittance fulfilment. The correlation between energy consumption and the climatic conditions is the base of the proposed method. The input data are seven climatic characteristics. Due to the sociocultural context of Latin America, the proposed method is estimated to have more possible acceptance and applications than other more complex methods, increasing the rate of buildings with an energy assessment. The results have demonstrated a high reliability in the prediction of the statistical models created, as the determination coe cient (R2) is nearly 1 for cooling and heating consumption

Modelo de cuantificación del consumo energético en edificación

The research conducted in this paper focuses on the generation of a model for the quantification of energy consumption in building. This is to be done through one of the most relevant environmental impact indicators associated with weight per m2 of construction, as well as the energy consumption resulting from the manufacturing process of materials used in building construction. The practical application of the proposed model on different buildings typologies in Seville, will provide information regarding the building materials, the subsystems and the most relevant construction elements. Hence, we will be able to observe the impact the built surface has on the environment. The results obtained aim to reference the scientific community, providing quantitative data comparable to other types of buildings and geographical areas. Furthermore, it may also allow the analysis and the characterization of feasible solutions to reduce the environmental impact generated by the different materials, subsystems and construction elements commonly used in the different building types defined in this study.La investigación realizada en el presente trabajo plantea la generación de un modelo de cuantificación del consumo energético en edificación, a través de uno de los indicadores de impacto ambiental más relevantes asociados al peso por m2 de construcción, el consumo energético derivado del proceso de fabricación de los materiales de construcción empleados en edificación. La aplicación práctica del modelo propuesto sobre diferentes tipologías edificatorias en Sevilla aportará información respecto a los materiales de construcción, subsistemas y elementos constructivos más impactantes, permitiendo visualizar la influencia que presenta la superficie construida en cuanto al impacto ambiental generado. Los resultados obtenidos pretenden servir de referencia a la comunidad científica, aportando datos numéricos que podrán ser comparados en otras tipologías y ámbitos geográficos, a la vez que permitirán analizar y precisar mejoras en cuanto al impacto ambiental generado por los diferentes materiales, subsistemas y elementos constructivos habitualmente utilizados en las tipologías edificatorias definidas

Evaluating Environmental Impact in Foundations and Structures through Disaggregated Models: Towards the Decarbonisation of the Construction Sector

Having a tool in Spanish regulations to evaluate the sustainability of the construction process in a simple and efficient way (Annex 13 of the Structural Concrete Instruction EHE-08) means an advance with respect to regulations in other countries. However, the complexity of homogenising the conditions that affect the execution of each structure, which are of a very heterogeneous and variable nature, in order to be able to evaluate their contribution to sustainability within the same reference framework, is the greatest obstacle and can have a great influence on the representativeness of the obtained results. However, there are variables that, given their specificity and nature, are not contemplated in this methodology (dust, noise and vibration emission, transportation). This paper proposes a complementary disaggregated model to evaluate the sustainability of variables that are not considered, namely the transportation of materials to the worksite, the commute of workers, the construction process, the emissions of dust, noise and vibrations, as well as the necessary load tests. The results of the application of this model to the real case of the foundations of two singular buildings, show the importance that these previously unexamined variables can have when choosing the most sustainable technical solution in terms of CO(2)emissions

Sustainability Assessment in Singular Structures, Foundations and Structural Rehabilitation in Spanish Legislation

The objective of this work is twofold: to determine the scope of the tools currently available for the assessment of sustainability of structures in Spanish legislation; and to identify environmental aspects that have yet to be covered, especially in the case of foundations and of measures aimed at the structural rehabilitation of singular buildings. To this end, the method proposed in the Spanish Instruction of Structural Concrete is applied to the particular case of the supported foundations of the Cylindrical and Colonel buildings in the construction of the new Faculties of Law and of Work Sciences, of the University of Seville during the period between 2005 and 2008. This case was chosen for its special uniqueness and for its inclusion of environmental aspects that remain outside the scope of existing methods. Most of these aspects are also of great relevance in structural rehabilitation activities carried out in urban environments and neighbourhoods, where a major surge is currently underway due to the economic crisis that has hit projects of newly constructed buildings. By virtue of the work carried out in recent years in the field of sustainability and the environment by several research groups at the University of Seville, a number of alternatives are proposed for the quantification of those aspects that remain to be considered. These techniques are based on tools that allow the agents to intervene in a flexible and effective way in the project implementation phase

Cuantificación del Consumo de Agua en el Proceso Constructivo de Viviendas Unifamiliares Tipo. Estrategias de Minimización

The water consumption during the construction process is not resolved yet in Bolivia, in this sense, a methodology for quantification of water consumption in the construction process in a housing type is presented, this being the most built type of construction during the period this study was conducted. Establish the consumption of water per square meter built is reached with the methodology, data of water consumption is a projection of the same, taking into account the housing demand and necessary square meters that must be built to meet this demand and will establish the amount of water to be used. Against the alarming result arises strategies to minimize the consumption of water in the building process, coming to establish a significant reduction, and also its should raise in an objective way and almost immediate for the next constructions. This proposed methodology can be applied to other types of buildings in order to establish the quantification of water consumption in various civil works.El consumo de agua en el proceso constructivo, es un tema no resulto en Bolivia, en tal sentido se plantea una metodología para realizar una cuantificación del consumo de agua en el proceso constructivo en una vivienda tipo, siendo esta la más construida en el medio que se realizó el estudio. Con la metodología empleada se llega a establecer el consumo de agua por metro cuadrado construido, con los datos del consumo de agua se hace una proyección del mismo, tomando en cuenta la demanda habitacional y los metros cuadrados necesarios que se deben construir para satisfacer dicha demanda y se llega a establecer la cantidad de agua a utilizar, frente al alarmante resultado se plantea estrategias para minimizar el consumo de agua en el proceso constructivo, llegando a establecer una reducción significativa, la misma que se debe plantear de manera objetiva y casi inmediata en las próximas construcciones. Esta metodología planteada se puede aplicar a otro tipo de construcciones para poder establecer la cuantificación del consumo de agua en diferentes obras civiles

Conservación de recursos a través de estrategias de reutilización de edificios y de reutilización de materiales en el sitio

Rethinking buildings and construction activities is a fundamental step towards sustainable construction. Being one of the most materials consumers, changes to current practices in the construction industry are crucial in order to effectively reduce primary resources exploitation, as also to reduce the environmental impacts associated with it. End of life of buildings are opportunities to close the materials loop, by means of building renewal and recovery of components and materials. In this context, building reuse and on site materials reuse have shown to be the most preferable end of life scenarios when compared with off site reuse, recycling, energy recovery and landfill disposal. Moving from demolition to deconstruction is one of the changes that are supposed to happen. Another is to change the materials selection procedures in order to consider also reused materials as a valid option in architectural process. Therefore, surveys to assess reuse potential are needed prior to architectural design in order to look for reuse opportunities and reuse constrains both at the building level and materials level. Such opportunities and constrains comprise building adaptability, building conservation state, mechanical and aesthetic performance of materials, feasibility of components and materials recovery. However, existing buildings were not built to be deconstructed and materials recovery is a labor intensive task, facing obstacles as non reversible connections which usually destroy materials integrity. A case study for building reuse and on site materials reuse is here analised in order to illustrate the theoretical principles and goals that drive the reuse approach, highlighting the environmental benefits by keeping Embodied Energy and thus reducing the Global Warming Potential related to construction activitiesRepensar los edificios y las actividades de la construcción es un paso fundamental hacia la construcción sostenible. Siendo uno de los mayores consumidores de materiales, es crucial proceder a cambios en las prácticas actuales en el sector de la construcción para reducir efectivamente la explotación de recursos primarios, como también para reducir todos los impactos ambientales asociados. El fin de vida de los edificios son oportunidades para cerrar el ciclo de vida de los materiales, por medio de la renovación de los edificios y la recuperación de componentes y materiales. En este contexto, la reutilización de los edificios y la reutilización de los materiales en el sitio han demostrado ser la solución más preferible en la gestión de los escenarios de fin de ciclo de vida, en comparación con la reutilización de los materiales fuera del sitio, reciclaje, valorización energética y eliminación en vertedero. Pasar de la demolición a la deconstrucción es uno de los cambios que deberá de acontecer. Otro es lo de cambiar los procedimientos de selección de los materiales con el fin de tener en cuenta también los materiales reutilizables como una opción válida en el proyecto arquitectónico. Por lo tanto, se necesita estudiar el edificio para evaluar su potencial de reutilización antes del proyecto, con el fin de buscar oportunidades y restricciones a la reutilización, tanto al nivel del edificio como al nivel de los componentes y materiales. Tales oportunidades y limitaciones incluyen la capacidad de adaptación del edificio, su estado de conservación, el funcionamiento mecánico y condición estética de los materiales y, por fin, la viabilidad técnica y económica de la recuperación de esos componentes y materiales. Sin embargo, los edificios existentes no fueron construidos para seren deconstruidos y la recuperación de materiales se torna una tarea intensiva de trabajo, enfrentando obstáculos como conexiones no reversibles que normalmente destruyen la integridad de los materiales. Un caso de estudio para la reutilización de la construcción y la reutilización de materiales en el sitio está aquí analizado con el fin de ilustrar los principios y objetivos teóricos que impulsan el enfoque de la reutilización, destacando los beneficios ambientales al mantener la energía incorporada y reduciendo así el potencial de calentamiento global relacionado con las actividades de construcción