In recent years, the housing market in China has expanded tremendously due to economic development. Building envelopes have become more and more airtight because of improvements in building technology and concerns on energy conservation. But a lack of knowledge on domestic ventilation performance and difficulties in achieving suitable standards have led to more and more complaints from occupants, and reported cases of building related illness (BRI).

The Minimum Ventilation Rate standard for dwellings is essential not only to provide occupant health and comfort, but also to remove and dilute the dominant pollutants. The purpose of this survey is to clarify and compare the regulations, standards or guidelines of ventilation requirements for residential buildings of various countries. The studies are based on the many literatures and interviews with the specialists in building regulation.

Steel truss structures, covered with a PVC thin sheet of matt light colour, were used in recent time for the construction of three new classrooms in the University of Catania (southern Italy). Although the construction was fast and cheap, the classrooms proved to be uncomfortable in relation to thermal and luminous environment. A first analysis revealed that the drawbacks were caused by the ultra-lightweight of the structure as a whole, resulting in thermal discomfort.

The Sint-Pieterschurch in the city of Ghent is one of the largest churches of the city. It was built in the 17th century. The city council wants to use the church not only for its religious functions, but also for cultural activities as concerts and exhibitions. To be able to do this the thermal comfort of the visitors has to be guaranteed. At this moment the church has no central heating system. Gas heaters are used during services. Installing a central heating system will influence the humidity and moisture behaviour of the church.

This paper deals with the relevance of Computational Fluids Dynamics (CFD) results confronted tomeasurements carried out under uncontrolled thermal conditions. Experimental tests have been undertaken in a room and in a kitchen of an experimental house. Although the wall surface temperatures and the air intake temperature have not been imposed, the air change rates have been controlled during the measurements. Moreover, since measurements have been carried out in a real environment, air leakage has occurred at the walls.

Local control of ventilation in large buildings is considered to be a main issue in energy savings regarding the huge energy losses that are usually induced by such large volumes. An efficient ventilation system and the development of local control ventilation strategies could prevent large buildings from having an unsuited or overvalued ventilation and reduce significantly the energy consumption.

More than 700 million of measured data, 730 days, 55 dwellings: the HR-VENT hybrid ventilationdemonstration project applied in NANGIS (France) on a set of occupied collective dwellings is closely linked to its stakes. From January 2004 up to December 2005, the values of humidity, temperature, pressure, opening surface and gas appliance operation are saved every minute in all the wet rooms by specifically developed sensors.

For retrofitting as well as for new buildings a good airtightness is an important issue. In Germany, Austria and Switzerland about 1000 persons conduct blower door tests according to EN 13829 in order to characterize the air permeability of buildings. Also, preliminary measurements of the air barrier are made, often by the craftsmen themselves. Early measurements allow to repair leakages more easily than when the building is completed.

The article describes the influence of the supply air devices that are part of hybrid ventilation system which is being developed within a EU funded project RESHYVENT as a part of this project, on thermal comfort in living-room of a three-bedroom apartment. The supply air radiator and the supply air convector are compared. The fresh air is sucked through a supply air convector and supply air radiator respectively and the air leakage through the facade is assumed too. 2 variants, which cover different outdoor temperature and supply air temperature for each device, have been solved.

Our commitment to improve both air quality and energy savings in existing dwellings involves scopemeasurements campaigns. Constraints linked to the use of measurements material in these conditions, the keeping of their reliability all project long and their costs prompted industry to develop special devices for this kind of application. It is the case of this high accuracy manometer required for the wide demonstration project called HR-VENT (Nangis- France).