English

Treats development of generalised model of hourly air infiltration in residences. Describes its testing. Uses tracer gas measurements of infiltration in 9 research residences inColumbus, Ohio, under widely varying weather conditions. Estimates various linear and physical models against 7000 measurements. Measures and correlates weather parameters. Correlation coefficients ranged around 0.9 with an error between 0.1 to 0.36 air changes. presents Fortran algorithm.

Known principles for the prevention of rain penetration and air leakage are not being applied in practice. States that rain penetration requires the simultaneous presence of water, openings and a force ; the two-stage weathertightening or "open rain screen" separates the control of these factors and allows the production of a weathertight joint under practical conditions. Outlines the causes of air infiltration and gives brief case histories to illustrate the serious problems that can arise from air leakage.

States that current methods of estimating heat demand of buildings are very inaccurate, and so large safety margins are used which usually result in overestimating the necessary heating plant capacity. Describes computer program developed to improve the accuracy of heat demand calculations. Gives formulae used in the program for calculating heat demand, pressure conditions and air flow within the building. Gives example of the use of the program to calculate the effect of wind on an eight-storey residential building.

Derives equations for the calculation of air-change-rate in a room where carbon dioxide is being produced at a known rate using the measured initial and final concentrations of CO2. Also derives expression for the calculation of air-change-rate with no source of CO2 but a high initial concentration

Describes research project which aimed to quantify the difference between actual dynamic ventilation rates and natural ventilation rates predicted using a steady state model. 

Explains why house external shell and ventilation system must be treated as integral elements of a total system. Explains, using an analogous water system, why air leakage through shell is greater using push-pull ventilation than when using extract ventilation and why houses should be airtight.

Reports the investigation of the natural ventilation of three test houses. Describes the houses which were of standard design. Natural ventilation rates were measured using sulphur hexafluoride as a tracer gas. An energy audit was also performed using a fan to pressurize and depressurize the house and an infrared scanner to detect the leakage paths. The tracer gas measurements were converted to a format similar to thepressurization results by using a previously developed model. Gives results in the form of graphs.

Calculations of water vapour flow through walls and ceilings are frequently based on the permeability of building materials and implicitly assume that most of the vapour transport takes place by diffusion. Finds that this model is generally inval

Describes experiment to determine the effect of an evergreen windbreak on residential heat losses attributable to air infiltration. Eight-meter tall pines were arranged as an experimental windbreak to shelter a townhouse for nine weeks Air infiltration was measured continuously using SF6 as a tracer gas to compare air change rates before and after the windbreak. A dimensionless parameter was derived to distinguish between wind-and temperature-produced air infiltration and to determine the effects of wind direction.

Describes tests made on fifty different weatherstrips. Tests were made in the laboratory of airtightness, rigidity, ageing, load tests, freeze tests and wear tests. Strips mounted in windows were tested for ageing and resistance to driving rain. Gives test methods and results and discusses the characteristics of eight main types of strip.