Airtightness performance of the building envelope of dwellings in Spain. Characterisation and energy impact of air infiltration

Este trabajo aborda la caracterización de permeabilidad al aire de la envolvente de los edificios residenciales en España. Para ello, se propone una metodología con la que se ha estudiado una muestra representativa de casos, que ha generado una base de datos. El grado de permeabilidad al aire, evaluado mediante ensayos de presurización por medio de ventilador, muestra el comportamiento dispar de los edificios y un considerable potencial de ahorro energético. También se ha estudiado la relación entre diferentes características constructivas y el grado de permeabilidad al aire, y se han identificado los focos de filtración más comunes. El diseño inadecuado de las soluciones constructivas, así como la descuidada ejecución de los encuentros entre diferentes elementos, se han señalado como las principales causas que impiden envolventes más herméticas, y, en consecuencia, suponen los principales retos a afrontar en el futuro.Departamento de Construcciones Arquitectónicas, Ingeniería del Terreno y Mecánica de los Medios Continuos y Teoría de EstructurasDoctorado en Arquitectur

A graphical tool to estimate the air change efficiency in rooms with heat recovery systems

Producción CientíficaIndoor air quality in buildings must be guaranteed for the health and comfort of the occupants. In order to assess the ventilation strategy of a considered room, the parameter of the air change efficiency ( εa ) can be used. The objective of this work is to provide designers with a graphical tool for a reliable estimate of the value of εa of a room. The temperature gradient between the outdoor air supply and the indoor air is so low that the ventilation flow can be assumed as isothermal when high-efficiency heat recovery systems are used. By means of charts, the optimal location of the openings for a better εa can be determined during the design process, in order to subsequently apply them. It is concluded that it is very important to consider the εa in the case of openings located in facing walls given that its range varies between 40% and 65%. In contrast, its use can be obviated in the case of openings located in non-facing walls, as the value of εa obtained is close to 50%; this means a perfect mixing air flow pattern, which is the reference value for the estimation of the indoor air quality (IAQ) in the different national regulations.EPACRA: Lanzadera project (TCUE.6-LANZADERA 067/157541

Energy impact of the air infiltration in residential buildings in the Mediterranean area of Spain and the Canary islands

Air infiltration through the building envelope has already been proven to have a significant energy impact in dwellings. Different studies have been carried out in Europe, but there is still a lack of knowledge in this field regarding mild climates. An experimental field study has been carried out in the Mediterranean climate area of Spain and the Canary Islands in order to assess the air permeability of the building envelope and its energy impact. A wide characterization and Blower Door tests have been performed in 225 cases in Alicante, Barcelona, Málaga, Sevilla and Las Palmas de Gran Canaria for this purpose. The obtained mean air permeability rate for the 225 studied cases was 6.56 m3/(h·m2). The influence of several variables on airtightness was statistically analysed, although only location, climate zone and window material were found to be significant. Air infiltration has an energy impact between 2.43 and 16.44 kWh/m2·year on the heating demand and between 0.54 and 3.06 kWh/m2·year on the cooling demand.This work was supported by the Spanish Ministry of Economy and Competitiveness (BIA2015-64321-R) under the research project INFILES: Repercusión energética de la permeabilidad al aire de los edificios residenciales en España: estudio y caracterización de sus infiltraciones

Methodology for the Study of the Envelope Airtightness of Residential Buildings in Spain: A Case Study

Air leakage and its impact on the energy performance of dwellings has been broadly studied in countries with cold climates in Europe, US, and Canada. However, there is a lack of knowledge in this field in Mediterranean countries. Current Spanish building regulations establish ventilation rates based on ideal airtight envelopes, causing problems of over-ventilation and substantial energy losses. The aim of this paper is to develop a methodology that allows the characterization of the envelope of the housing stock in Spain in order to adjust ventilation rates taking into consideration air leakage. A methodology that is easily applicable to other countries that consider studying the airtightness of the envelope and its energetic behaviour improvement is proposed. A statistical sampling method has been established to determine the dwellings to be tested, considering relevant variables concerning airtightness: climate zone, year of construction, and typology. The air leakage rate is determined using a standardized building pressurization technique according to European Standard EN 13829. A representative case study has been presented as an example of the implementation of the designed methodology and results are compared to preliminary values obtained from the database

Educar la mirada, la mano y el pensamiento a través del arte próximo. Una propuesta didáctica para dibujo artístico I

Trabajo de Fin de Máster del Máster en Profesor de Educación Secundaria Obligatoria y Bachillerato, Formación Profesional y Enseñanza de Idiomas, curso 2014-2015.[ES]El siguiente trabajo es resultado de todos los conocimientos adquiridos a lo largo del curso, tanto de las diversas asignaturas como del período de prácticas en la Escuela de Artes de Salamanca. Se ha realizado una propuesta didáctica de carácter innovador e integral para Dibujo Artístico I con el objetivo de favorecer el proceso de enseñanza aprendizaje. En este sentido, se pretende educar al alumno poniendo en valor el arte cercano de artistas actuales de la región

Impact of Air Infiltration on IAQ and Ventilation Efficiency in Higher Educational Classrooms in Spain

Indoor air quality (IAQ) in educational buildings is a key element of the students’ well-being and academic performance. Window-opening behavior and air infiltration, generally used as the sole ventilation sources in existing educational buildings, often lead to unhealthy levels of indoor pollutants and energy waste. This paper evaluates the conditions of natural ventilation in classrooms in order to study how climate conditions affect energy waste. For that purpose, the impact of the air infiltration both on the IAQ and on the efficiency of the ventilation was evaluated in two university classrooms with natural ventilation in the Continental area of Spain. The research methodology was based on site sensors to analyze IAQ parameters such as CO2, Total Volatile Organic Compounds (TVOC), Particulate Matter (PM), and other climate parameters for a week during the cold season. Airtightness was then assessed within the classrooms and the close built environment by means of pressurization tests, and infiltration rates were estimated. The obtained results were used to set up a Computational Fluid Dynamics (CFD) model to evaluate the age of the local air and the ventilation efficiency value. The results revealed that ventilation cannot rely only on air infiltration, and, therefore, specific controlled ventilation strategies should be implemented to improve IAQ and to avoid excessive energy loss

Educación XX1 : revista de la Facultad de Educación

Título, resumen y palabras clave en inglés y españolResumen basado en el de la publicaciónLos cambios en los planes de estudio que se producen en la ETS Arquitectura de la Universidad de Valladolid, generan algunos problemas en la asignatura de Geometría Descriptiva. A través de un Proyecto de Innovación Docente (PID), se busca dar solución a los problemas planteados mediante nuevos métodos de enseñanza dentro y fuera del aula y una mayor interacción entre alumnos y profesor, de modo que la geometría no sea algo abstracto, ajeno al ejercicio profesional del arquitecto. Se pretende estructurar una nueva asignatura que capacite al alumno de técnicas y recursos no solo gráficos y espaciales, sino de trabajo en equipo, cooperación, capacitación, suficiencia y autonomía que le ayuden en el desarrollo de su futura profesión. Se diseña un curso basado en la gamificación que permite a los alumnos enfocar la asignatura desde un punto de vista más lúdico, con el objetivo de motivarlos e involucrarlos. A partir de esta experiencia en la que se comparan los sistemas tradicionales y los propuestos, se presentan las conclusiones obtenidas de este nuevo método en lo que respecta a la tasa de abandono, rendimiento académico y percepción del método de enseñanza por parte de los alumnos. La incorporación de técnicas basadas en el juego tiene un efecto motivador para los alumnos, que descubren una manera de aprender jugando lo que antes percibían como una asignatura tediosa.ES

Implementation of a Ventilation Protocol for SARS-CoV-2 in a Higher Educational Centre

The most recent research confirms that airborne transmission may be the dominant mode of SARS-CoV-2 virus spread in the interior spaces of buildings. Consequently, based on some prescriptions that implemented natural ventilation during face-to-face lessons in a university centre, an experimental characterization of several complementary options aimed at reinforcing the prevention and safety of the occupants was carried out. The action protocol adopted was based on the combination of mandatory natural ventilation, a maximum contribution of outdoor air supply in the air conditioning system, and the use of filtering devices located inside the classroom. All the strategies were incorporated concomitantly with necessary compliance with the basic conditions of social distance, occupation, use of masks and guidelines for use and cleaning within educational buildings. The suitability of this protocol was further evaluated throughout the teaching day with students and teachers by measuring the CO2 concentration. The results showed that the measures implemented successfully removed the possible pollutants generated inside

Airtightness of residential buildings in the Continental area of Spain

Producción CientíficaLa infiltración juega un papel relevante en cuanto al rendimiento energético de los edificios. Muchos países europeos ya han establecido normas que tienen como objetivo limitar el desperdicio de energía a través de la envolvente siguiendo las directrices de la Directiva europea sobre eficiencia energética de los edificios. Sin embargo, en los países mediterráneos todavía existe un desconocimiento en este campo. Se ha llevado a cabo un extenso estudio con el fin de caracterizar las fugas de aire a través de la envolvente del parque de viviendas existente en la zona de clima continental de España. Se muestran los resultados de 129 viviendas analizadas, incluyendo diferentes tipologías y periodos de construcción. Se realizaron pruebas de puerta sopladora y se utilizaron imágenes térmicas para localizar las rutas de fuga. Se encontró que las viviendas unifamiliares eran más herméticas que los apartamentos, dado que la tasa media de permeabilidad al aire a 50 Pa (q50) era de 5,4 m3/h·m2 y 6,8 m3/h·m2 respectivamente. La tasa media de renovación de aire a 50 Pa (n50) fue de 6,1 h-1 para viviendas unifamiliares y de 7,1 h-1 para viviendas multifamiliares. Sin embargo, se encontró gran dispersión de resultados y valores extremos. Además, se evaluó la influencia de varias características de la construcción en los resultados de permeabilidad

An envelope airtightness predictive model for residential buildings in Spain

Producción CientíficaThe need for airtightness control is a reality given its impact on buildings' energy use and Indoor Air Quality (IAQ). For the past few years, this fact has resulted in energy performance regulations establishment that involves airtightness requirements in many countries in Europe and North America. In this sense, efforts should not only be focused on new buildings, but also existing ones. Considering that around 90% of the built stock in the EU is expected to still be standing in 2050 and that almost 75% of the buildings are energy inefficient, attention must be paid to retrofitting actions. Airtightness predictive models have become useful in the decision-making process and to estimate input values in energy performance simulation tools. So far, several predictive models have been developed in different countries. However, specific construction systems and practices lead to a lack of consensus regarding the impact of different factors on airtightness performance. Therefore, the applicability of existing models is limited to their specific contexts. This paper presents a predictive model for envelope airtightness, which was developed from a database that contains a fully characterised representative sample of the residential building stock in Spain. A General Linear Model (GLM) was considered to assess significant variables related to the age of the building, typology, building state, construction system, and dimensions. As a result, a predictive model is presented and validated. Overall, even if some limitations were identified, the relevance of the model proposed is warranted from the statistical point of view. The airtightness predictive model presented offers a procedure for airtightness estimation of residential buildings in Spain.Ministerio de Economía, Industria y Competitividad (grant BIA2015-64321-R