This paper presents results of air leakage measurements on brick walls and concrete block walls, used as outer or inner leaf of a cavity wall. The results are obtained using a pressure box on a series of test walls. The variable parameters that are examined: workmanship, pointing of the joints andplastering of the inner leaf. Out of the results can be concluded that, in general, only a plastered wall can guarantee a sufficient airtightness.

The mixing system (even called the dilution system) is normally used throughout the world to supply air to a premises. In the mixing system you blow air at high velocity into the room at a temperature which gives you the wanted room temperature. If the system works perfectly, you will have the same temperature and concentration of contamination in the whole room. That is because the supplied air and the air in the room is mixed due to induction.

A study has been made, both experimentally and analytically, on the characteristics of thermal performance of high-rise buildings using a simulated model building with five floors and a number of exterior openings under various temperature distributions. The effect of the temperature variation on the location of the neutral pressure level (NPL) was of particular interest of the present study.

It has been estimated that 15% of the energy used for building services in the United Kingdom is consumed in industrial buildings. A large proportion of this is thought to relate to infiltration and ventilation. There has been very little information produced concerning infiltration rates in industrial buildings because of the difficulty in making accurate measurements. During the past three years, British Gas has made ventilation and building leakage measurements in a number of industrial and other large buildings in the UK.

Air change rates are measured by an IR-gas-analyser coupled with a microcomputer which is programmed to control measurements as well as data acquisition and evaluation. The implemented programs provide an instant access to results. The experimental equipment is installed in compact form on mobile units. Measurements have been taken in a university laboratory by using the decay- and constant-emission-method to examine air change rates under various conditions. Typical results are presented and show where each of the two methods is more appropriate.

A computerised portable unit for measuring the ventilation efficiency by the tracer gas technique is described. The hardware of the unit is designed from readily available equipment. The software of the unit is menu-driven to be operated by computer non-experts. The software include several analytical models of ventilation processes and in the present study, age analysis and the air exchange efficiency are discussed.

For more than four years air infiltration measurements have been made on two nearly identical side-by-side test houses in Gaithersburg, Maryland, USA. This testing of the complete seasonal weather influence on air infiltration has, in the past two years, included constant concentration tracer gas measurements (CCTG). These multizone air infiltration measurements have added further detail on the response of air infiltration into the house to weather changes and the variation of air infiltration between different house locations.

The construction and performance of a dynamic wall house are described. It is suggested that such houses function much like the traditional houses with leaky walls and active chimneys. Only here ventilation is controlled while a significant part of the energy required to heat the ventilation be lost. A model is proposed to explain how much walls function at relatively low ventilation rates. The approach promises to improve indoor air quality and thermal envelope performance at reduced construction and energy costs.

This paper outlines the development of guidelines for the design and installation of ventilation systems installed in energy efficient homes constructed under the R-2000 Home Program of Energy, Mines and Resources Canada. The guidelines represent one of the first initiatives to develop comprehensive requirements for the design and installation of mechanical ventilation systems for residential buildings in Canada. The guidelines outline requirements for a continuous supply of ventilation air to dilute and therefore control contaminants produced from dispersed sources in a home (e.g.

In order to avoid demage to the health of occupants, annoyance or reduction in amenity and demage to the building fabric the concentration of indoor air pollutants has to be held below pollutant specific levels. One appropriate measure for the control of concentration is ventilation. In several national and international activities in the past, among others in the IEA's Annex IX "Minimum Ventilation Rates" and standardization efforts in Germany and other countries, ventilation rates have been defined which should meet both indoor air quality (iaq) requirements and energy conservation.