English

States that much of the heat loss in American houses can be traced to generic faulty details in design and construction. Discusses style of housebuilding in the United States. Notes vast majority of American houses were built of wood. gives a broad classification of typical houses into seven types. Notes variation in energy performance with climatic region. States intention to undertake case studies to assess the energy performance of each type.

A sequel to the report "Air leakage through the openings in buildings", abstract. no 286. Reports investigation of the effect on air leakage of increasing the clearance around a sash window. Gives results of experiments in the form of graphs showing leakage for different wind velocities, different clearances, and with and without weatherstripping.

Describes apparatus used to measure air leakage through windows. Gives details of windows with and without weatherstripping. Gives results in the form of graphs in two sections. 

The amount of air leakage through window gaps in buildings depends on the width and length of the gaps, the pressures across the buildings and the resistances in the air circuit. Reviews the ranges of these factors for Britain and gives results of measurements within these ranges for standard metal and wooden windows and for weather-stripped windows. Gives two methods of estimating the air flow through gaps in complete windows.

Describes a system which measures the rate of air infiltration in buildings using sulphur hexafluoride as a tracer gas. Discusses two methods for evaluating the infiltration rate,the decay method and the constant concentration method. The system automatically operates a portable electron capture detector /chromatograph and samples air on a one-minute cycle. In the decay method the slope of concentration vs time on a semilogarithmic plot can be used to compute infiltration rate.

Reviews use of tracer compounds to demonstrate the transfer of pollutants from one local area or city to another. A study of gaseous compounds resulted in the selection of three suitable materials:sulphur hexafluoride, bromotrifluoromethan andOctafluorocyclobutane. These materials are all non-toxic, rare in the atmosphere and can be readily dispersed from tanks.Describes two systems developed to detect tracer gases. Sensitivity of 10-5 p.p.m. was achieved for sulphur hexafluoride without concentration of the sample. Gives method for collectingair samples and analysing them.

Describes apparatus and test method used for measuring air leakage through metal windows in the laboratory. Gives results for different types of windows and summarises air tightness standards in Japan and other countries.

Describes operation of thermal imaging cameras with a display monitor detecting infra-red radiation. Since temperature differentials of 0.20C are significant for insulation of buildings, camera must be used to limits of its sensitivity and monitoring procedure must be carefully chosen. Treats measurement limitations in field of building. Uses details of thermographic surveys to illustrate some difficulties of measurement and analysis. Emphasises importance of correct inspection procedures for particular situation.

Wind tunnel test conducted on a scale model of a classroom show that, provided the test air speed is kept in excess of about 3mph, it is feasible to use models for predicting, with good accuracy, the air-flow conditions in and around full-scale buildings. In the case of low-pitch roofs the height of the stagnant zone set up as a result of flow separation occurring at the windward eaves of a building is influenced by wall height rather than by roof pitch.

Developes a simple procedure for calculating exterior wall pressure differences and air infiltration rates for various wind velocites and direction by applying the pressure data obtained from a wind tunnel model study to a computer model building. Gives separate expressions for air infiltration caused by stack action and by wind and an expression for the combined effect. Gives example of infiltration calculations compared with computer results and finds good agreement.