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Ventilation technologies are the key aspects to reach the target of nearly zero energy buildings. From 1st January 2016 on ventilation units have to comply with minimal energy efficiency criteria according EU Regulation No 1253/2014 of 7 July 2014 implementing Directive 2009/125/EC of the European Parliament and of the Council. Furthermore, residential ventilation units will have an energy label according EU Regulation No 1254/2014 of 11 July.

Conventional Displacement Ventilation (DV) system has been installed in an office of a Zero Energy Building (ZEB). Enhanced DV (EDV) system, consisting of fans mounted to the chair, which has been demonstrated in laboratory and field environmental chamber studies earlier was implemented for the first time in a full-scale office environment to assess its effectiveness of improving the thermal sensation of the occupants. Objective measurements and subjective assessments were conducted in the office with 12 occupants over a period of 2 weeks.

The paper presents a numerical methodology to assess the natural ventilation. UrbaWind is an automatic computational fluid dynamics code. It was developed to model the wind in urban environments. The turbulence modelling, namely the dependence of turbulence length on the distance from wall, and the model constants were calibrated in order to reproduce with good agreements flow separation around buildings walls and pressure coefficient field on façades. Numerical results match well with the experiments: separation patterns and pressure field on walls in dense urban areas.

As an alternative to adopting active architectural systems (mechanical systems) and taking advantage of the resources provided by nature, natural ventilation contributes interesting solutions to control the thermal balance and the air quality, and it is applicable in a variety of climate zones. Natural ventilation also solves some of the more common problems of mechanical systems, such as the noise factor and installation and maintenance costs.

This paper describes Post Occupancy Evaluation survey and physical measurements of five families living for one year or longer in five houses located in Germany, Austria, France and UK, all part of the Model Home 2020 project. The houses are built according to Active House principles and focus on high performance on indoor environmental quality, energy performance and environmental impact. The survey is carried out seasonally during the test year when the family lives in the house to capture seasonal variations. Physical measurements were made in all main rooms of the houses.

Ventilation plan for smoking room must deal with pollutants since they affect the air quality of adjacent rooms. Although ventilation plan typically maintains a negative room pressure to remedy this problem, the transport of indoor air pollutants between rooms is affected by moving objects, such as human movement and door opening. The purposes of this study were to evaluate the effects of moving objects on the rate of transport of indoor air pollutants and to propose a method of controlling contamination for smoking room.

The objective of this study is to develop an approach concerning the integration of volatile organic compounds (VOCs) emissions due to office equipment in computational fluid dynamics (CFD) simulations, in order to assess the indoor air quality (IAQ) in offices. The transport and diffusion phenomena of VOCs are taking into account in the CFD model by means of conservation equations of the mass fraction, written for each VOC that is intended to be considered in the simulation.

A mass balance model is used to examine the impact of two ventilation (1 /h and 2 /h) and recirculation (7 /h and 14 /h) rates on concentrations, exposure to and intake of ozone (of outdoor origin) and secondary organic aerosols (SOA) derived from the ozone initiated chemistry in indoor environment. Measured data from several experimental studies conducted by the authors in a 236m3 field environmental chamber (FEC) configured to simulate an office are used for the mass balance model evaluations.

The trend toward minimizing ventilation of houses in order to reduce energy consumption for heating and cooling leads to an increase in indoor air pollution. The deterioration of indoor air quality (IAQ) negatively affects human health, safety, productivity and comfort. In order to evaluate the scale of this influence IAQ assessment has to be performed. However, the IAQ itself is not well defined and a number of parameters are considered as its indicators. In this work we compared carbon dioxide and volatile organic compounds as indicators of indoor air quality.

The present study aimed at assessing six commercially-available in-duct air cleaning devices which are designed to be mounted in the central ventilation system of offices or commercial buildings. The selected devices use different air cleaning technologies: mechanical filtration, electrostatic precipitation, gas filtration, ionisation / cold plasma, photocatalytic oxidation (PCO) and catalysis under UV light.