Discusses ventilation requirements to achieve acceptable air quality. In many cases, this would lead to unacceptable energy costs, so instead recommends setting standards for heat-exchanger systems, for filters that can control particulates, hydrocarbons and radon gas, and for details such as flow direction and system maintenance. Also standards for 'pollustat' systems should be encouraged by which four surrogate pollutant levels would be kept below suggested threshold levels in all conditions of building use and occupancy.
Discusses methods of preventing condensation: dehumidification, ventilation, controlling vapour flow; insulation and heating. Particular attention is paid to interstitial condensation and condensation in roofs
Discomfort due to stuffiness and adverse temperature gradients may occur in well insulated rooms with low levels of natural ventilation. Using methods previously applied to studies of convection in the atmosphere, a model of the room air movement
The advantages and disadvantages of various ventilation systems have been assessed in Germany over the past four years. The programme covered research in unoccupied test rooms as well as in occupied buildings. Results are presented, and the possibilities and limits for energy saving while meeting comfort requirements are discussed.
In order to determine ventilation performances in hot arid regions a transient program was simulated for a single room with glass windows. The calculations were done on climatic data of a typical city close to the central desert of Iran. Results indicate that the incident solar radiation to the room has a high influence on the room air temperature.
Evaluates results of the 'Ventilation in Residential Buildings' research programme of the German Federal Ministry for Research and Technology. It was found that conventional ventilation methods based on infiltration and window opening cannot secure proper air quality and at the same time provide energy conservation and user comfort, nor can intelligent ventilation habits be expected of the average user, for subjective and objective reasons. All ventilation systems evaluated had shortcomings.
In new buildings, the requirements for indoor air quality and energy efficiency cannot be met with natural ventilation. In renovations of existing buildings it is, however, often difficult or uneconomic to install a mechanical system. What is often forgotten is that the conditions for natural ventilation will have changed, even if no alterations are made to the ventilation system.
Describes a new ventilation strategy for retrofitted buildings. The system consists of two units including heat recovery, fan, filter, etc, which are installed in the window openings. They are operated in opposite directions which are periodically reversed. When desired, the unit is stopped and used as an airing panel. In laboratory tests the specified values were achieved. The heat recovery proved so efficient that no air heating was needed even at the lowest temperatures. Some noise and freezing problems were reported.
Some of the problems for designing ventilation systems for retrofitted buildings are presented. Measurements were taken in two public buildings in Helsinki with three ventilation systems of different types. In these two buildings only a balanced mechanical ventilation system seemed to fulfill therequirements for a satisfactory and healthy indoor environment.