English

The problems associated with the measurement of ventilation rates and air movement patterns in large single cell buildings which were unoccupied and unheated were investigated using the tracer gases nitrous oxide and sulphur hexafluoride. 

Presents methods for the measurement of air flow rates, including methods for measuring flow in ducts, at exhaust and supply air devices and for air change rates for using tracer gas.

Looks at the separate requirements of ventilation and heat recovery. Discusses the energy cost of ventilation. Gives example calculations for four different situations to show how much saving an air-to-air heat exchanger can provide. Savings depend on ventilation rate, climate and energy price.

A database on the airtightness performance of houses built according to current construction practices (1980 to 82) was established, province by province, across Canada. Airtightness tests were conducted using the fan-depressurisation method and the results were compared by province, builder, house style, and house size. The survey shows considerable variation in the leakiness of the houses when the results are compared by province. Less variation in airtightness exists when the houses are compared by builder, house style, and house size on a provincial basis.

Measures air permeability of 21 facades of occupied dwellings. Investigates what proportion of air permeability is due to various gaps (moveable sections) and joints (between fixed sections) in 12 of the facades. Results show that the contribution of joints to air permeability is greater than mentioned in the Dutch Standard NEN 3661. This standard stipulates conditions with regard to the manufacture of facade elements. It is apparent that the gaps of 5 out of the 12 measured facades do not meet the minimum requirements of the standard.

A spunbonded polyolefin air infiltration barrier (AIB) was installed immediately beneath the siding of a 5 year old ranch-style house. The AIB reduced the heating energy consumption by 27% during the first heating season and is expected to reduce the heating load by 28% over the remaining life of the house.

Reports on pressure tests carried out on the Kasarminkatu 24 building (a museum of architecture) in Helsinki. The fans in the building were used to measure airtightness of the building envelope, and the tightness of windows and doors was measured separately by the guarded box method. The tightness of the building envelope was good (2 ach at 50 Pa). 70% of total air leakage came through the wooden roof structure, and only 5-10% through the windowstructure. Three alternative mechanical ventilation systems were also studied in the same building to assess their impact on indoor climate.

For the transient analysis of the thermal and moisture conditions in multilayer constructions a numerical algorithm and a computer program based on the Crank-Nicholson method and quasi linearisation are formulated. Temperature and moisture content are used as transport potentials. In energy balance equations and conditions, convention and accumulation of moisture, the diffusion flow of water vapour, the capillary and surface diffusion flow of liquid water and the viscous flow of humid air and water are considered. The boundary layer and interfacial balance equations are derived.

Describes a simple device which pressurises an enclosed volume of air adjacent to individual components in the building fabric. The air flow through the crackage is measured and the interdependence of the flow rate and pressure is examined. Windows, floors, loft traps and suspended ceilings are examined. A simple relationship is found to be applicable to individual components but no universal relationship is found for a general range of components with superficially similar cracks.

Notes the trend to installing windowless kitchens, bathrooms and W.C.s in the internal zones of dwellings. Describes a research project to measure for internal kitchens the energy consumption and emission of equipment, the total daily energy consumption, air temperatures, air humidity values during cooking, comfort and air speed. Illustrates the test kitchen and gives the results of measurements of around 100 days of simulated operation for a household of four. Notes the consequences for recommended normal and peak ventilation rates.