The IEA project Annex 27, Evaluation and Demonstration of Domestic Ventilation Systems,have come to the stage that simplified tools can be presented in a total scheme. At earlierAIVC conferences some of the tools have been presented in separate papers and still the toolsare under development. In this paper a more general approach of the usage of the tools is to bepresented.The work is based on the joint work of participants from both AIVC countries (CAN,F, NL, S, UK, USA) and non-AIVC countries (I, J).

Costs are one of the main decision factors for the selection of domestic ventilation systems.This often leads to a ventilation system that just meets the requirements of buildingregulations at the lowest initial costs. Decision makers are often not aware of the impact of thequality of the ventilation system on life cycle costs, not only for the ventilation system itselfbut also for the building, as a result of complaints or even damage due to a poor functioningventilation system.

Natural passive stack ventilation (PSV) consumes no power and so produces no harmfulemissions, has no running cost, no noise of operation, requires little maintenance and becauseit involves no moving parts, operation is reliable. However, virtually all PSV systems aredesigned and constructed without incorporating heat recovery, leading to wasteful heat loss.The goal of the research reported here, is to develop a passive stack ventilation system withheat recovery for use in naturally ventilated buildings.The heat recovery unit is based on the heat-pipe principle.

The paper deals with energy consumption and heat recovery in office buildings with natural ventilation. Net energy consumption for ventilation is calculated for 7 European countries. The calculations are done with various air flow rates and occupancy. The calculations shows differences between the seven countries, but the net ventilation heat loss is substantial for all. Norway and Sweden will benefit most from heat recovery. Several heat recovery concepts for natural ventilation are presented.

As everybody knows, today the air quality of an indoor environment may have several effectson our health; the beginning of serious breathing pathologies and of some forms of cancer,are with no doubt due to the presence of polluting and extremely noxious agents in the placeswe most frequently use.That's the reason why it is very important that indoor rooms are correctly aired also in ourhomes where, due to several incidental factors, the healthiness of the environment is stillguaranteed by the mere and discretionary operation of users of opening the windows.In considering the growing attenti

This paper considers the role of passive stack chimneys in controlling indoor thermalconditions in the vernmlar houses on the volcanic island of Santorini . The quality of theenvironment within these dwellings is disputable, mainly because of the high humidity levels.A monitoring study was carried out in four actual dwellings in Santorini, two built on thesurface and two excavated into the soft volcanic rock. The temperature and relative humidztyof their main space and their chimneys were monitored and compared to the simultaneousexternal conditions.

The performances of self regulating natural ventilation devices (devices of which the openingsection varies as function of the pressure difference across the device) strongly depend on thetype of building and its leakage characteristics. In like manner, the climatic conditionsstrongly impact on the achieved ventilation rates. As a result, it is not possible to express thepotential benefit of self-regulating natural ventilation devices in an unambiguous way. This isnot contributing to a good understanding of the potential of such devices in daily practice.

There are certain conditions which are of interest when designing for natural ventilation ofcommercial buildings. These are:- summer cooling- indoor air quality in winter- night-time cooling.For the first two conditions it is necessary to determine the distribution of open areas to givethe desired distribution of flow rates. Since one is dealing with openings whose position andbasic geometry are known, the problem is relatively simple compared to general ventilationproblems.

This paper identifies the significance of pollution at five sites amongst the worst on the British mainland hence indicative of other polluted areas within Europe. Three sites are located in London and one each in Birmingham and Cardiff. The pollutants examined are NO2, SO2, O3 and PM10. Newly proposed DOE figures defining poor air quality have been used to re-examine the frequency of excess pollution episodes between 1992-1995. The results identify the most appropriate periods for natural ventilation of offices in urban areas in terms of the hour in a day and time of year.

Within the EU project NATVENT, which deals with the application of natural ventilation in office type buildings, one of the items to be studied was controlled air flow inlets. Natural air supply is a key part in the design of natural ventilation in offices. In cases these air supplies are designed in the wrong way one may expect complaints in terms of draft and stuffiness. Size and controls on inlets are vital elements in design. Controlled air inlets may help to overcome the problems of draft and stuffiness, and may contribute to an energy efficient design of the building.