English

Examines the use of radioisotope tracers to measure ventilation rates of simple and multiple enclosures. Discusses accuracy of the methods in relation to results obtained in an experimental room with controlled ventilation. Describes an instrument which measures ventilation rates directly, following release of aradioisotope tracer. Demonstrates its accuracy and operating advantages.

Describes retrofitting a wood-frame residence in three stages to reduce its energy requirements for heating and cooling. The three retrofit stages comprised reducing air leaks; adding storm windows; and installing insulation in the floor ceiling andwalls. The house was extensively insulated to evaluate energy savings and changes in air infiltration rates. Concludes that retrofits produced only marginal reduction in air infiltration rates and attributes this to the original tight construction of the house.

Describes experiments in a wind tunnel on a model of a tall building of rectangular plan to show the effects of variation in wind velocity with height and the variation of local wind pressures with angle of wind. Discusses the effect of rounding the corners of the building.

Explains forces causing stack effect in multi-storey buildings and suggests ways of reducing air leakage. Mentions that stack effect makes the operation of doors difficult and interferes with the operation of dampers.

Compares wind pressures measured on a single-family dwelling with results obtained from a 1:50 scale model in a turbulent boundary layer. Shows that fluctuating components of surface pressures far exceeded mean or steady pressures and are well correlated over sizeable roof areas. Suggests that certain current provisions are marginal for tributary areas and excessive for localised area such as ridges, eaves and corners. Describes procedure for expressing loads on both localised and extended roof areas in terms of mean pressure coefficients and a peak factor.

Summarises research into air leakage. Describes field studies of air leakage of exterior walls, the heat loss caused by stack effect and smoke movement caused by wind and stack effect. Describes mathematical model for air leakage and flow patters of multi-storey buildings. Discusses implications of results on building design. NOTES general survey only.

A study made to confirm the values given in german standard DIN 4701. considers theoretical natures of air permeability and the k-value as they concern windows. Finds that infiltration through windows without weather-stripping depends to such an extent on the quality of manufacture and fitting that essential differences between single-glazed, double-glazed and double windows scarcely exist. Finds no real difference between woodenand metal frames when new, but after normal wear and tear an average value of 3m(3)/h for each metre of gap at 1mm pressure difference is acceptable.

Gives general data about windows in the experimental dwellings and the transport of air through small openings. Describes method for calculating the rate of air infiltration through windows as a function of the pressure difference between both sides of the construction. Presents results for each type of window graphically in several ways. Gives figures for cracks between movable construction parts.

Describes method for simulating natural wind boundary layer in a conventional, short working section, aeronautical wind tunnel. Boundary layers, which may be as thick as one-half of the working section height are generated by spires at the working section inlet. This approach is used to measure mean wind pressures and pressure spectra on a model of a tall building in downtown Montreal. Measurements are repeated using the long roughness fetch technique for boundary layer generation and results from the two methods compared.

States heat load on buildings due to wind is dependent on the shape of building, wind direction and wind speed. Gives theoretical calculation for the heat loss due to wind based ongerman standard DIN 4701. Discusses fundamentals of fluid dynamics and the practicalities of wind tunnel tests. Recounts tests made of a block of flats in Munich. Pressure distribution due to wind was determined by a wind tunnel test on a model, giving c-profiles for different wind directions.