ventilation systems

Particulate matter (PM) is one of the most critical pollutants affecting indoor air quality (IAQ). Hence, reducing the exposure of occupants to indoor PM pollution is critical. Ventilation systems for commercial and residential buildings are instrumental for achieving this goal.

Various field studies have shown that in a vast majority of European countries the quality of installed residential ventilation systems is poor, with a large proportion of systems having significantly lower installed flow rates than the required values, or having poor energy performance due to flaws in design, installation or operation. This paper analyses the potential impact of different policy options for an EU-level approach for inspection of stand-alone ventilation systems in residential buildings until 2050.

Trends in home heating and cooling in the US are resulting in less mixing of air within dwellings, either due to not using central forced air systems, or to reduced loads and runtimes in high performance homes. This study examined the use of zoned ventilation systems using a coupled CONTAM/EnergyPlus model of new California dwellings, including a 1-story single-family dwelling and a single apartment unit. Zoned and unzoned ventilation systems were simulated for exhaust, supply and balanced fan types.

The primary purpose of ventilation and air-conditioning system is to ensure internal comfort conditions through a continuous supply of air and maintaining the assumed indoor parameters. High air velocity in the occupied zone may result in an uncomfortable feeling of the draft, cooling effect, or local discomfort. The subjects of the study are linear diffusers, which depending on the purpose, are installed in ceilings, floors, or walls. Models may vary widely in their shape, number or size of slots/nozzles, and the length or shape of the deflector blades.

The book of proceedings of the 13th International BUILDAIR Symposium "Airtight Buildings, Thermography and Ventilation Systems in Practice",  held on June 2-3  2023 in Hannover, Germany. Contains 36 abstracts.

Worldwide, the demand for airtightness tests of tall buildings with a height of approximately 100 m is increasing. This report provides information on the planning and measurement concept for testing the entire building as a “single-zone” and presents the results and findings of the airtightness tests. The test set-up and the tests as such are based on the Passive House Institute's Guide to Measuring Tall Buildings [5] which includes recommendations that go beyond the ISO 9972 standard.

Weltweit steigt die Nachfrage nach Luftdichtheitsprüfungen von hohen Gebäuden mit einer Höhe ab ca. 100 m. Dieser Bericht informiert über das Planungs- und Messkonzept zur Prüfung des gesamten Gebäudes als „Single-Zone“ und stellt die Ergebnisse und Erkenntnisse der Luftdichtheitsprüfungen vor. Der Prüfaufbau und die Prüfungen als solche basieren auf dem Leitfaden des Passivhaus Instituts zur Vermessung von Hochhäusern [5], der Empfehlungen enthält, die über die Norm ISO 9972 hinausgehen.

Purpose of the work 
According to the two Swiss building standards Minergie-P and Minergie-A, individual dwelling units are considered measuring zones for airtightness, irrespective of whether they are in a new, renovated or modernized building. The Minergie standards focus on comfort between the dwelling units and the energy losses caused by infiltration. 
Do zone measurements meet relevant requirements? Which requirements do the zone measurements fail to meet?

Ziel der Arbeit/Fragestellung 
Für die beiden schweizerischen Energiestandards Minergie-P und Minergie-A werden bei der Luftdichtheit die einzelnen Nutzeinheiten als Messzonen betrachtet, egal ob Neubau oder Erneuerung / Modernisierung. Im Vordergrund steht der Komfort zwischen den Nutzungseinheiten nebst den energetischen Verlusten durch Infiltration. 
Werden bei Zonenmessungen die Anforderungen eingehalten? Welcher Anteil erfüllt die Anforderungen nicht? 

Purpose of the work 
When dealing with very airtight buildings and buildings with flexible airtight roofing felts it might take several minutes for the differential pressure and air flow to level out after having changed the fan speed. Taking premature readings of the values causes measuring errors. The lecture provides pointers for test teams to avoid such measuring errors.