We are working on a residential project (5-Story) that is being certified v4 BD+C. The dwelling units are naturally ventilated. The monitoring requirement for natural ventilation in v4 states to provide either one of the following measures:  1) Direct exhaust airflow measurement 2) Automatic indication devices on window openings 3) Carbon dioxide monitoring.

These options do not seem feasible, as there are major cost implications. Does anyone have experience or a better strategy to successfully meet the requirement for ventilation monitoring in naturally ventilated residential buildings?

We have toilet exhaust and dryer exhaust from the unit. Does anyone have any experience in monitoring the exhaust w/alarm and if that would meet the requirement ?