Design principles

Outlines forces causing air leakage through openings in a building. Discusses likely leakage paths and states importance of identifying these and improving the air tightness of walls, windows, floors and roofs.

Application of design principles in practice

Discusses in general terms the importance of attending to detail in construction. Gives examples of faulty design and construction.

Ventilation rate in modern flats. Luftskiftet i nyere boliger.

Reports measurements of air change rates carried out in the living rooms of 39 flats built during the last 20 years using Freon 12 as a tracer gas. Ventilation rates ranged from 0.3 to 2.9 changes per, hour, the average being 1.3 changes per hour. Air temperature, humidity and wind speed were recorded and the ventilation rates corrected for wind speed and temperature. Notes large ranges in ventilation rates for similar flats.

Indoor air pollution in Rotterdam homes.

Reports study of 800 paired samples of indoor and outdoor smoke and SO2 concentrations of 60 Rotterdam homes. Finds that smoking increased the amount of smoke found in living rooms and the data suggest that newer houses tend to have less SO2 in the living rooms than older houses. On average living rooms contained approximately 80% of the smoke and 20% of the SO2 measured simultaneously outdoors during 24 hour periods. Estimates probability of having more SO2 in the living room than outdoors is less than 2%.

Wind baffles. a proposed method for limiting the influence of wind on the ventilation pattern in livestock houses. Winddruckkap een voorziening om de invloed van de wind op het ventilatiepatroon in stallen te beperken.

Animal houses such as piggeries and cattle sheds are commonly ventilated using extraction fans in the ridge of the building. Fresh air is introduced through wide openings. These openings are screened by a baffle. Describes improved design of baffle which caters for a constant pressure difference between the inside and outside of the house.

Sneaky invisible things: air currents of two classic passive solar houses.

Presents diagrams showing the behaviour of air currents in two passive solar houses. Suggests some straightforward means by which repetitive patterns of discrete currents can be engineered. An appendix briefly outlines the operation of a discrete current flat plate collector with a 65 - 75% normal winter efficiency.

Pressure measurements on wind tunnel models of the Aylesbury experimental house.

Presents further measurements of wind pressures on models of the experimental Aylesbury house of the Building Research Establishment (U.K.). following a previous paper in which mean pressure coefficients only were compared, this stud compares fluctuating pressures as well. In these tests, the upwind hedges of the full scale site were modelled, but found to cause little difference to the velocity profiles and to the measured pressures.

Metal stud walls.

Describes exterior walls of metal studs and gypsum board, used as infill walls in frame construction of industrial, commercial and high-rise residential buildings. Discusses problems of high thermal conductivity of such walls, and the application of a vapour barrier to reduce air leakage.

Measurement of air leakage of houses.

Reports tests of the air leakage of 24 houses made using a fan to depressurize each house. Gives a table of results including indoor humidity, air-particulate levels, energy consumption and comfort conditions for each house. Comparison of test results with calculated values for air leakage suggests than doors and windows account for only a fraction of the total. Finds some correlation between indoor humidity, air-particulate levels and leakage.

Infiltration and air leakage comparisons : conventional and energy-efficient housing designs.

Describes results of measurements of air leakage, surface pressures and air infiltration for several conventional and energy efficient houses located throughout the United States. The measurements are compared with predicted infiltration obtained from a simple model combining measured air leakage values and average surface pressures. It was found that within limits therewas reasonable agreement between measurements and predictions. Particular features of the energy efficient houses which reduce air leakage, and therefore air infiltration, are described.