English

This paper discusses the advantages of utilizing air flow windows in hot climates and the technical and functional aspects of engineering air flow window systems into the buildings. Air flow windows offer several advantages to building owners such as maximum space comfort, more usable floor space, energy and monetary savings and possibilities to use daylighting in the optimal way. Additionally air flow windows seem to be easily combined with all commonly used air conditioning systems.

This paper reports on recent developments and future activities in the Netherlands on ventilated facades. The Billiton International Metals building in the Hague is an early example of this. The research for this specific building has formed the foundation for further research on ventilated facades. A literature search has been carried out, and an extensive measurement programme in combination with a computerized model has been announced.

Attic ventilation is compared with other means of ceiling heat flux reduction in low cost housing. A simple steady state mathematical model has been run with climatic data for a summer day of Porto Alegre, Brazil. The increase inceiling thermal resistance has proved to be the best improvement, but it is expensive. The greatest proportion in ceiling heat flux reduction is in the natural ventilation range and forced ventilation adds little to it. As natural ventilation does not imply extra cost, it is very important in low cost housing and should be optimised.

This paper examines the excess ventilation losses arising from window opening behaviour by occupants and using data from a number of sources relates these losses to the outside air temperature. These excess ventilation losses alter the shape of the total heat loss predictions and bring these more into line with the energy consumptions measured. Excessive ventilation by open windows is shown to negate the benefits of increased fabric insulation.

The passive perfluorocarbon tracer (PFT) technique for determining air infiltration rates into homes and buildings was evaluated in an environmental chamber. 

Multizone infiltration requires extensive and complex information about the flow characteristics and pressure distribution inside the building, and thus has been too difficult to develop and to validate. By relying on lumped parameters for the description of air flow distribution in a building, a simplified model is produced. This paper describes the parameters and considerations involved in the development of the multizone infiltration model.

Buildings in cold climates must provide an indoor environment that is markedly different from that outdoors. The materials and components of the exterior envelope are subjected to large variations in conditions and greater demands are placed on the indoor environmental control system. Air pressure differences across building elements are augmented by buoyancy forces that influence air movement and indoor air quality. The potential for moisture condensation on and within the envelope is increased as is the danger of freezing in liquid systems.

Describes a reasonably accurate method for estimating air infiltration for engineers or energy auditors who are not specially trained in infiltration research. The method requires two steps: field measurement of the building properties, and calculation of the infiltration from weather data and themeasured properties. Fan pressurization techniques are described and how to use them to measure the air tightness of the building envelope, and the procedures required to make infiltration predictions with the Lawrence Berkeley Laboratory infiltration model.

This paper presents a simple method for estimating the total air change rate of a house with or without mechanical ventilation. The proposed method can be used to assess the effect of a mechanical ventilation system on total air change rates. It can also be included in existing simple computer programs forestimating heating requirements for houses. A calculation procedure is also presented for sizing mechanical ventilation systems for houses. This procedure can be used to estimate the forced ventilation rate required to achieve the desired total air change rate.

Measurement of air exchange rates, ages of air, and nominal and local ventilation efficiencies in large buildings is often complicated by the building size and compartmentalization, and by the presence of multiple ventilation systems. To allow characterization of the ventilation process in such buildings, a unique experimental system, that employs multiple tracer gases, is being developed at Lawrence Berkeley Laboratory. The tracer gases are sulfur hexafluoride and five halocarbons. The system is designed to be non-obtrusive, highly automated, and relatively easy to ins tall in buildings.