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The peak electrical demand of office building VAV systems will be reduced by about 1.2 Kw/1000 Ft2 by employing an Integrated Systems Demand Control Technology (ISDCT) sequence to reduce peak intake flow by about 56%.Supply, return, and exhaust fan energy decreases with reduced airflows and pressures; and chiller system energy is saved by reduced cooling coil loads.The ISDCT sequence continuously computes zone contaminant concentrations allowing compliance with reference standards.

The IEA ECBCS Annex 36 deals with the energy retrofit of educational buildings. Researchers from 10 participating countries from Europe and the US are collecting information on retrofit measures and case studies and are developing an energy concept adviser for technical retrofit measures. This internet-based computer tool for decision-makers is the main outcome of the annex. One of the most important inputs to the tool is the collection and assessment of case studies, which is also presented in a specific report.

This paper deals with the real behavior of a humidity controlled air inlet, regarding to relative humidity and temperature. It has been often heard, that relative humidity is not the best indicator for detecting a need of ventilation in main rooms (living room and bedrooms) because it is season dependant (the absolute humidity outside varies in a wide range from winter to summer, which should lead the air inlet to be closed in winter and open in summer).

In the survey study ‘Kantoor 2000’ the HVAC-system of several large office buildings in Flanders was monitored. Some of these buildings use air humidity control, most of them not. This triggered the question : why? In this paper the humidity control strat

The building envelope is primarily an environmental separator, which allows indoor spaces to bemaintained at different conditions from the outside environment. Intentional humidification during the heating season is a common practice in cold climates. Moisture escaping from a humidified building due to air leakage through flaws in the air barrier system can negatively affect the durability of the building envelope.

The use of natural ventilation systems continues to be a popular feature in low energy, sustainable building design. One feature of natural ventilation is that, depending upon the prevailing climatic or thermal conditions, the airflow through a ventilator can be bi-directional. Aerodynamically, the ventilator, depending upon its construction, may not perform in the same way for the two different flow directions.

The knowledge of indoor air humidity in the design phase is important to decide on the appropriate moisture control measures to prevent moisture problems in building components. Because of the uncertain nature of most of the factors affecting the indoor humidity, its accurate prediction in the design phase is not possible. To overcome this problem, the concept of Indoor Climate Classes has been introduced and used in Europe since its early development in the Netherlands in the 1970s up to its recent introduction in a European Standard on the hygrothermal performance of building components.

For energy savings, DCV systems are more and more used in ventilation systems. In France, in nonresidential buildings, these systems are generally controlled by either a CO2 sensor, or an opticalmovement detection (infrared). The part of the study we present here was to determine laboratorytests methods to assess the performances of optical sensors for ventilation application. The pointwas to characterise them by checking their detection in front of some determined movements orevents.

A Demand Controlled Hybrid Ventilation System is a two-mode system using natural forces as long as possible and electric fans only if necessary. Sensor technologies are used to establish the exact required airflow for indoor air quality and thermal comfort to a minimal energy demand. A large part of the Dutch dwellings are foreseen with a ventilation system consisting of natural supply with mechanical exhaust. Fan power for these systems typically is 30 - 40 W (Specific Fan Power 0.7 - 1.0 kW/(m3/s)). Small improvements lead to a laboratory reference of 21 W.

In France, in non residential buildings, these systems are generally controlled by either a CO2 sensor or optical movement detection (infrared).The part of the study we present here was to determine :- laboratory tests methods to assess the performances of CO2 sensors for ventilation application.- the working performances of these sensors, and particularly the long term stability in a meeting room.- a methodology to assess the performances of CO2 DCV system in French technical agreementThe main results of this study are :- it is easy to characterize (to calibrate) the sensors- the long term