Natural Ventilation

In Germany, Austria and Switzerland (DACH-Region) natural ventilation is a very common way of ventilation. However, there is no standard defining principles of natural ventilation in the DACH-Region. According to ASHRAE 62.1-2010 natural ventilation is acceptable if the required openings are permanently open or have controls that prevent openings from being closed during periods of expected occupancy. This is not common in the DACH-Region. Occupants are expected to open the windows whenever necessary, and seem to be used to it. In Germany there are at least regulations for ventilation of workplaces in the “Arbeitsstättenverordnung” (engl. Ordinance on Workplaces) Part ASR A3.6. Section 5.4. Intermittent natural ventilation is allowed and there are regulations about the frequency and the duration. (However it is up to the user to manually open the window). Frequency: Office: every 60 minutes Meeting: every 20 minutes Duration: Summer: 10 min Spring/ Autumn: 5 min Winter: 3 min So with IEQp1 in the current state, we fear that many buildings won’t reach a LEED certification. ASHRAE 62.1-2010 seems to be even more an issue for existing buildings as these won’t comply with the requirements without extensive refurbishments. What we also see critical is the mandatory equipment of each naturally ventilated room with a CO2-monitor. Natural ventilation is a widely accepted strategy (mechanical ventilation has only been established in the last 10-20 years). We think, that we definitely need an ACP for natural ventilation to account for the different building culture.