Natural Ventilation in Multifamily Residential

Omer, Hopefully this response isn't so late that its no longer useful to you. To address each space type you listed: -Bathrooms: must meet the applicable exhaust rate from Table 6-4 -Storage rooms: if only occupied occasionally and for short periods of time they would not need to be ventilated (see the definition for occupiable space in Section 3). Otherwise they would need 0.12 cfm/sf per Table 6-1 -Changing rooms, in-unit corridors and entry halls: I would consider all of these as part of the "Dwelling unit" occupancy category in Table 6-1, and their floor areas would simply be lumped together with the other spaces in the units. They wouldn't each need a dedicated ventilation system if they part of a large open space which is ventilated as a whole. My interpretation is that only the portions of the spaces outside of 25 feet from operable windows need to be included in the calculations for the engineered system.