Peter Wouters

Duct leakage in European buildings : status and perspectives

A large number of modern European buildings are equipped with ducted air distribution systems. To investigate the implications of duct leakage, a field study was performed on 42 duct systems in Belgium and France. The measurement data confirm the findings of the few earlier experimental investigations on these matters in Europe. In our sample, the leakage rate appears to be typically three times greater than the maximum permitted leakage adopted in EUROVENT 2/2 (Class A). The advantages of tight ducts are illustrated with a theoretical case study on a balanced ventilation system with heat recovery. It indicates that the overall effectiveness of the system reduces drastically if the ducts are leaky. The savings potential of an airtight duct policy at the European level is calculated (a) based on estimates of the number of buildings equipped with mechanical ventilation systems, and (b) assuming market penetration scenarios of rehabilitation techniques. At the European level, the cumulative savings potential over a period of 10 years appears to be in the region of 10 TW h (36 pJ).

Ventilation requirements in non-domestic buildings and energy efficiency

Abstract This paper focuses on the importance of the level of ventilation requirements on the energy demand of non-domestic buildings. At present, we observe a tremendous difference in the ventilation requirements in various countries as well as at the European level. Variations by a factor of 10 of the ventilation rate requirement can be found in the proposal for European standard CEN (European Committee for Standardisation) prENV 1752 depending on the ‘cleanness’ of the building. The present paper develops these problems and makes a comparison with the situation in other areas like thermal comfort and lighting requirements. Results of a practical case study are included.

Practical experiences with IR-controlled supply terminals in dwellings and offices

Ventilation is necessary to provide good indoor air quality to occupants in buildings but can be a major energy consumer. Results from two experimental studies carried in several dwellings and in office buildings show that the use of presence detection (infrared sensor) for controlling ventilation has a potential for substantial reductions in the heating energy consumption. A simulation study of the impact of infrared spectroscopy (IR) controlled ventilation on the yearly heating energy consumption was performed and it showed that reductions from 27% to 47% can be obtained in well insulated office buildings.