Windbreaks probably are more important for reducing infiltration of cold outside air into houses than for reducing convective heat losses. It is difficult to estimate the magnitude of tree effects on energy use for space conditioning on a year-round basis, but past studies suggest that trees have the potential to reduce winter fuel consumption by 10-25%. Describes several studies of trees as windbreaks and for summer shade. Discusses location of trees with respect to buildings.

Describes a method used for measuring the local air tightness of sections of buildings. Notes its superiority to a previous system developed by Siitonen V. in 1982. Illustrates the device schematically and explains its operation.

Roof space ventilation is necessary to evacuate water vapour to avoid condensation and to conserve the wooden roof supports. It has been affected by 1. increased insulation, 2. snow screens fitted under the roof, 3. increased humidity due to

Indoor radon concentrations have been measured in a 13 year old two story concrete building of the University of Texas at Dallas. Variations of the radon concentration from the basement to the second floor in offices, classrooms, laboratories, storage rooms, corridors and other locations have been measured. Dependence of the above concentrations on the location and ventilation rates have been studied.

Distinguishes two categories of leaks in buildings for cold storage. Thermal leaks through parts of the construction with poor thermal insulation and air leaks through openings in the walls allowing a more or less free flow of air. Outlines principles of infrared radiation and thermography. Discusses applications for both types of leaks. Under the conditions of high emissivity of the surface to be studied, and absence of local heating or cooling (sun,wind, rain), thermography is an effective method for the detection of thermalleaks and a powerful tool for localizing air leaks.

Deals with a code providing directives for design and construction of cold stores, drafted by the Foundation for Development of Refrigeration Technique (Stiftung Ontwikkeling Koeltechniek). Gives threshold values for admissible pressure difference and admissible measure of non-tightness, and values forthe required pressure equalizing opening, depending on nature and size of the cold room.

The largest contribution to population exposure from natural radiation arises from the inhalation of the decay products of radon in indoor air. In most instances the dominant source of radon within buildings is the subjacent ground. However, building materials do contribute to the radon concentration in indoor air, and in some circumstances may provide the major source. Thisreport reviews some of the literature on radon emanation from soils and building materials world-wide.

An accurate determination of air renewal rate and connective exchanges between units was needed for study of the solar units of the experimental building LESO, in both an occupied and empty state. The CESAR compact equipment for tracer gas (nitrous oxide) measurement was developed. This unit uses a microcomputer to perform a simultaneous and periodical gas analysis in 10 locations. Three tracer gas methods can be used: decay, constant concentration, and continuous flow. The device and regulating program work well with low rates of concentration (100ppm of nitrous oxide).

Discusses the effects of air infiltration and air change rate on temperature and humidity of indoor air. Attempts to quantify the relationship between surface temperature, thermal bridges, thermal resistance and indoor climate.

Retrofitting for air infiltration is undertaken for two principal reasons, to provide greater comfort and to save energy. Qualitative and quantitative measurement of air penetration is an essential prerequisite for planning anefficient retrofit for air infiltration. Describes methods of measurement with two examples of single family houses in sheltered and exposed locations.