pressurization

Measures the airtightness of various types of 25 residential units (9 detached houses and 16 apartments) using the fan pressurization technique. Shows the relationship between the pressure difference across the building envelope and the volumetric flow rate of air as well as the ratio of the effective leakage area of one building element to the total leakage area. Compares the airtightness of various types of houses in different countries using the valueof the effective leakage area per floor a at a pressure difference of 10 Pa.

Describes pressurization tests conducted by the National Testing Institute on 3 large industrial buildings. Sets out equipment and methods used including atracer gas method to calculate air flow through the fan rather than the usual measuring duct. Gives construction and volume details of buildings measured.

Describes the testing of 8 federal office buildings (size from 3000 sq.m. - 45000 sq.m.) for their air infiltration characteristics, as part of the NBS program to develop diagnostic test methods for evaluating the thermal integrity of federal office buildings. Performs tracer gas tests in the autumn, winter and spring to evaluate both the ventilation of these buildings during occupied periods and the natural air leakage under various weather conditions.

Describes some new theoretical and experimental techniques developed by British Gas to investigate the ventilation of buildings. These include:< 1. The multi-cell model "vent" for predicting ventilation rates< 2. "Autovent", the multi-cell constant concentration tracer gas technique used for measuring ventilation patterns in buildings.< 3. Pressurization techniques for measuring air leakage in buildings.< Gives a selection of results from applications of these techniques to show their scope.

Subjects 11 private dwellings at Taby and 5 at Brunna (all 2-3 yrs old) to repeated airtightness tests over a period of two years. Finds the largest leakage is 2.5 ach and the mean leakage is 1.6 ach. Immediately after its completion, the air tightness of a building undergoes a certain deterioration, after which it stabilizes. Over the 2yr. measuring period the changes are small, and could all be attributed to occupancy effects. Leakage paths occurat the junctions of wall and ceiling and wall and floor, and at service entries.

Presents a review of the main methods used for the study of air movement. Includes sections on physical modelling (wind tunnel modelling etc), analogue (water and electrical) models of air movement, mathematical models and digital computer analogues, and full scale investigations including pressurization andtracer gas techniques.

Studies the predictive accuracies of infiltration-pressurization correlation models by subjecting a group of identical homes in Freehold NJ to both pressurization and tracer gas measurements of infiltration. Compares infiltration and pressurization test results. Uses four air infiltration models to predict the infiltration rates in the houses, and compares these predictions with the measured rates. Makes predictions using several different values of the inputs required for the models, and studies the effects of varying these inputs.

States that a comprehensive sealing program should be considered in every residential energy conservation program. Covers the theory of air flow in a structure , how this theory is converted into a practical service, and theeffect on the house including humidity and air quality concerns. Describes the infiltrometer, a pressurization device used to detect air leakage, how to useit and how to interpret data.

Gives a summary of the work in testing of different energy-saving retrofits performed in dwellings in Sweden. The report is based on work done at the Swedish National Testing Institute and the National Swedish Institute for Building Research carried out during the winter 1979-80. Thermography methods, pressure test method, tracer gas measurements and heat flow measurements wereused in 91 houses, which were retrofitted. Describes different test methods and discusses results of measurements.

Briefly overviews some of the available instrumentation and techniques that could be used by the home-owner, or professional auditor to evaluate energy use in houses. Includes descriptions of the "blower door" method for evaluating air leakage, and some tracer gas techniques for measuring air infiltration.