English

When attempting to determine heating/cooling requirement of a home a difference in infiltration can drastically affect heating/cooling requirement imposed on air conditioning system. Describes "the super sucker" machine designed to depressurise homes so that infiltration can be measured under simulated windconditions and each area of leakage isolated. Illustrates machine photographically. Gives method of determining air change rates. Summarises test data for several homes which indicatethat infiltration could be effectively reduced by use of various caulking compounds.

Outlines parameters governing air infiltration. Discusses problem areas of house to house comparisons of air leakage. Deals primarily with tracer gas procedure as compared with pressurisation/depressurisation approach. Describes testing in townhouses of recent construction as well as in a number of older homes of varied design. Uses roof-top laboratory test chamber to examine relations between wind effects, buoyancy effects and building openings and how they effect air infiltration. Uses results to clarify evaluation of air infiltration.

Describes how in 1960-62 National Research Council of Canada conducted air infiltration measurements on 2 single-storey houses using helium as a tracer gas, followed in 1967-68 by measurement of air leakage characteristics using house pressurisation technique. Describes procedure developed from these tests for calculating infiltration rates. Gives equations for calculating infiltration due to stack effect and that due to wind action. Gives equation for combined effect.

U.S. ventilation systems have been reported to require as much as 50-60% of total energy consumed in buildings and have become popular targets for energy conservation methods. Notes serious concern that arbitrary changes to codes and standards are being proposed in the name of energy conservation which could jeopardise health, safety or welfare of building occupants. Traces evolution of ventilation codes and standards in us.Treats difficulties encountered with measurement and direct control of indoor air quality. Notes common guide values for air contamination used.

Presents and explains derivation of simplified heat transfer equation as part of an averaging method to enable perceptive home owner to determine air infiltration. A winter month isselected and the gas meter read daily. Explains how with these minimum data and summary data from us weather bureau average infiltration for the month, plus other useful data such as relative magnitude of conduction vs. infiltration losses can be determined. Demonstrates technique by worked example for a demonstration house.

Describes field measurements of thermal transmittance using portable guarded hotbox equipment on 2 types of concrete walls. Air leakage measurements of these same 2 types of concrete systems were made in the laboratory. Describes test methods. Illustrates measurement equipment and effects of infiltration diagrammatically. Concludes that it is not known how typical either wall system was, and further research is underway to evaluate other types of concrete building systems for air infiltration effects on thermal transmittance.

Describes wind tunnel measurements made on a model of a tall building surrounded by lower buildings under various combination of wind speed, wind angle and air temperature. Gives method for calculation of air infiltration rates and describes the computer program used. Concludes that air infiltration is a strong function of wind direction. Finds that maximum air infiltration was produced by a wind that approached at 0 deg and the minimum air infiltration occurred at 75 deg wind angle.

Describes different types of weatherstrips and reports ageing and deformation test on strips and tests on air tightness and closing force. Concludes that tubular strips provided the highest degree of airtightness in both windows and doors, while angle strips were only slightly inferior in performance. Air leakage was considerably greater for strips of expanded and foam plastics and fibre strips. Tests on ageing properties indicated that special rubber mixtures such as silicone rubber and epdm were preferable to p.v.c.

Suggests many ways of reducing outdoor air admitted to a building. Notes importance of measuring minimum air flow to ensure adequate ventilation. Suggests measuring the concentration of CO2 in indoor atmosphere and using the results to control incoming ventilation. Describes simple and inexpensive implementation of the technique.

Reports measurements of ventilation rate in specially designed low energy office building. Air change rates were measured using sulphur hexafluoride as a tracer gas and air samples were analyzed for carbon dioxide. Gives tables of results. Discusses analysis of ventilation from CO2 data. Concludes that most of the spaces in the building were operating at or above recommended levels.