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Infiltration has a considerable impact on both, energy efficiency and occupant comfort in buildings. Due to the complexity of the analysis of this phenomenon in buildings, the verification methods are very important for its diagnostics and evaluation. In this paper, the matter of infiltration in buildings is being considered referring to both, calculation models and methods, as well as through current standards and regulations in the EU and Serbia. Different valorization methods are presented and analyzed regarding their characteristics, applicability, and complexity. Finally, preliminary infiltration measurements with a pressurization test, conducted on selected buildings of Belgrade housing stock are presented and compared with values defined by the current regulations in Serbia. Results pointed out current problems and the need for improvements regarding the treatment of infiltration in local regulations and practice. Инфилтрација има значајан утицај у разматрању питања како енергетске ефикасности тако и комфора у објектима. Због сложености анализе овог феномена, методе верификације показале су се као веома важне приликом дијагностиковања и евалуације инфилтрације. У овом раду се питање инфилтрације разматра у односу на моделе и методе прорачуна, као и тренутне стандарде и прописе у ЕУ и Србији. Разматране су различите методе верификације кроз анализу и поређење њихових карактеристика, применљивост и сложеност. Представљена су и прелиминарна мерења инфилтрације одабраних објеката у склопу стамбеног фонда Београда тестом притиска удувавањем која су упоређена са вредностима дефинисаним важећим прописима у Србији. Резултати су указали на тренутне проблеме и потребу унапређења третмана инфилтрације у локалним прописима и пракси.

Ventilation in built environments is essential to guarantee a good indoor air quality and a reduced probability of infection related to virus transmission. Measuring ventilation-related parameters is not easy and currently two methods can be adopted: pressurization and tracer gas decay. The pressurization test measures the airtightness of the building, whereas the tracer gas decay test measures the actual (site- and climate-specific) air exchange rate. Finding a relationship amongst the results provided by the two tests would be very useful in view of an exhaustive characterization of the building ventilation, but it still remains an open challenge for the scientific literature. The present paper aims at investigating the criticalities in correlating the two methods; thus, an experimental campaign was performed in a multi-room dwelling performing both air permeability and air exchange rate measurements in the entire dwelling and in parts of it. A detailed uncertainty budget of the two methods was also carried out in order to perform metrological compatibility analyses. The results of the campaign highlighted that the actual air exchange rates of the dwelling present a huge variability (from 100, with an exponential decrease as the wind velocity increases. Thus, adopting constant conversion factors could significantly overestimate the actual ventilation of the building.

The study is focused on the evaluation of air permeability and ventilation rate in Italian classrooms. Measurements were performed in 16 naturally ventilated classrooms located in Cassino, Central Italy. Classrooms’ airtightness was evaluated through the fan pressurization method. Air exchange rates where both estimated from the blower door results and measured using a CO2 decay test method. The effect of the periodic manual airing of the classrooms (through window and door opening) was also investigated performing CO2 and particle number concentration measurements during the school time.

Producción Científica, The primary objective of this paper is to present the use of a steady model that is able to qualify and quantify available natural ventilation flows applied to the energy retrofitting of urban residential districts. In terms of air quality, natural ventilation presents more efficient solutions compared to active systems. This method combines numeric simulations, through the utilization of Ansys Fluent R15.0® and Engineering Equation Solver EES®, with on-site pressurization tests. Testing consists of the application of the seasonal pressure gradient on the building’s envelope and the calculation of the ventilation flows in three climatic representative conditions (summer, winter, and annual average). Through the implementation of this methodology to existing buildings it is possible to evaluate the influence of the built environment, as well as key parameters (relative height of the dwelling, number of vertical ventilation ducts, and airtightness of windows) of available natural ventilation., CITyFiED project, which has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration activities under the Grant Agreement number 609129