English

Currently, various studies have demonstrated some doubt about the accuracy of the orifice equation when applied to the calculation of cross-ventilation. As a result, a computational fluid dynamic (CFD) simulation is considered the best method of analyzing cross-ventilation properties under present conditions. However, repetition of CFD analysis to determine the optimum ventilation performance is particularly complex. Accordingly, a flow network model that corresponds to cross-ventilation was developed and suggested as a more efficient means of determining the optimal opening conditions.

In 1998, Persily published a review of commercial and institutional building airtightness data that found significant levels of air leakage and debunked the myth of the airtight commercial building. This paper updates the earlier analysis for the United States by including data from over 100 additional buildings. The average airtightness of 28.4 m3/hm2 at 75 Pa is essentially the same as reported by Persily in 1998. This average airtightness is in the same range as that reported for typical U.S.

Studies on buildings’ airtightness have shown that several issues can arise from uncontrolled airflow leakages in buildings (e.g., higher energy cost, thermal comfort and health of occupants, building components and equipment preservation). The new French

In today’s architecture, innovative concepts, such as double skin facades, for the building skin are developed to improve the energy performance of a building and at the same time improve the indoor climate of the building. Various types of double façades

Ventilation in buildings is necessary first for hygienic reasons and also to preserve the building structure. This is more essential, today, because the buildings are more and more airtight, mainly due to energy regulations. It is also evident that air renewal energy losses and fan consumption become more and more important in relation with the total energy consumption of buildings. Nevertheless, many defaults are encountered on installed ventilation systems. It seems necessary to check the installations, at the starting up and regularly in time, and not only when the problems occur.

This field study was organized to determine the ventilation required to maintain acceptable air quality in a retail store using the ASHRAE Standard 62-1989 performance-based procedure. Pollutant concentrations and ventilation rates were measured in a large retail store during four one-week intervals. The measurement intervals were each separated by three months to allow different weather conditions and mixes of retail stock to be present over the one-year field study in a cold continental climate.

DayMedia and MulCom are multimedia teaching packages targeted at architects and building engineers, as well as students. While DayMedia is concerned with daylighting in architecture, MulCom covers human comfort and the energy performance of buildings. Most of the content is related to thermal comfort, although acoustics and visual comfort are covered as well. The development of the packages has part-funded by the European Commission and coordinated by the Low Energy Architecture Research Unit (LEARN) of the University of North London.

PASLINK is the grouping of 14 European research institutes involved in the performance assessment of the thermal and solar characteristics of building components under real climate conditions. Most of the members are performing semi-standardised tests using the PASSYS/PASLINK test cells. IQ-TEST is the European thematic network project aiming at further developing common quality procedures for testing, calibration, data gathering, cleaning and analysis, interpretation of test results and scaling/replication to real buildings, maintenance of test infrastructure.

Spectral radiative properties of panel glass and coatings are measured, like transmittance and reflectance. The coating influence on the panel behavior is presented. Material properties like index of refraction and the absorption coefficient are determined. Such determination takes place in the visible and near infrared region of the electromagnetic spectrum. The property determination is performed with transmittances and reflectances measurements in different wavelengths from 400 to 4000 nanometers. Total visible and solar transmittance is calculated, based on these data.

Solar shading devices can significantly improve thermal comfort and reduce cooling loads and potential glare problems in highly glazed buildings. This paper describes results from an extensive measurement program that started in 1997, covering external shading devices, products placed between two panes (interpane), and internal shading devices. Measurements of the total solar energy transmittance (g-value) have been performed using a double hot-box arrangement placed in a real climate.