In this paper the methodological benefits and constraints of conventional climate chamber research in comparison to the field-based alternative are discussed. The discussion of methodology is extended to the discipline of environmental psychology and with a questionning on how engineers have come to dominate a research topic that falls so clearly within the scope of psychology.

In this paper the assessment of moderately cold environments with two different methods : the PMV method and the IREQ method. The applicability of the comfort criteria is analyzed too for a more general assessment of cold environments.

Major ventilation developments covering systems, measurements and design methods have taken place over the last 25 years. Our understanding about the impact of ventilation on the indoor environment and energy use has also evolved. This paper outlines these developments. Many future challenges are considered including minimum ventilation rates, energy efficient cooling, cost effective heat recovery and the development of calculation techniques.

This study deals with the ventilation performance of two storey dwellings employing stack effect ventilation to satisfy the overall ventilation requirement. The SRF (Supply Rate Fulfillment) index was used as a ventilation performance index. The experiments were implemented to measure effective fresh air rate by using tracer gas in a test house. Following are the results of the experiments and the theoretical calculations. The measured air change rate and the SRF value were fairly close to the theoretical calculation.

For retrofitting of existing dwellings MVHR is seldom applied, despite the potential in energy saving and improving thermal comfort and indoor air quality. Major barriers and limitations for application are lack of space, especially for the supply ducts and the MVHR units as well as the complexity of execution. Also initial costs are an important barrier. Limiting supply ducts could be beneficial for application in single family dwellings. In a study some configurations with simplified air supply with MVHR in single family dwellings have been investigated.

Recent studies in Switzerland showed that in large non residential buildings, which can be compared for typology and ventilation needs, the consumption of electricity for mechanical ventilation can vary considerably from case to case. Moreover in such a building it represents a percentage not negligible of the whole consumption of electricity. We had a confirmation of that behaviour with a study we made during 1999-2000 on a set of eighty air treatment units of the Civic Hospital in Lugano (Southern Switzerland).

The main objective of the demonstration project LabSan is the innovative energetic retrofitting of a research laboratory building (3724 m² net floor area) which can serve as an outstanding and guiding example for a large number of existing laboratory buil

An idea to build a demonstration house fitted with a hybrid ventilation system arose when Brno University of Technology joined the RESHYVENT project. There has not been much attention paid to the residential ventilation in the Czech Republic. Window airing and passive stack ventilation are still the most common ways of ventilation in residential buildings. In this context a decision was made to build a house equipped with a demand controlled hybrid ventilation system.

To get closer from comfort and energy levels of new buildings conciliating economical viability for the big retrofitting market : the challenge opens the way to the most innovative ventilation systems. In this context was born a new hybrid ventilation system mixing demand-controlled components and low pressure assistance fan. HR-VENT is an exceptional large-scale monitoring launched in France in the suburb of Paris in order to measure the effectiveness of this new system, as well as to improve the knowledge on the hybrid and standard natural ventilation.

The Dutch housing stock consists for about 70% of single family houses with an average N50 of about 7-9 ACH and for 30% of apartments with an average N50 of about 3-4 ACH.New single family houses are much more airtight. In the period 1970 to 2000 the air tightness increased to an N50 of about 3 - 4 ACH. Apartments have nowadays about the same or a slightly better air tightness then before 1970.Another trend is the downward tendency of occupant numbers per dwelling.