What should be installed on outdoor air intake and exhaust openings?

Installing a screen on outdoor air intake and exhaust openings is crucial for several reasons. Firstly, it helps prevent vermin, such as rodents and insects, from entering the building through these openings. This is important for maintaining indoor air quality and preventing pest-related issues that could compromise the integrity of the structure and cause health concerns for occupants.

Moreover, screens can also protect these openings from debris, such as leaves or twigs, which could obstruct airflow or damage the ventilation system. Proper airflow is essential for ventilation systems to function effectively, and any blockage can lead to inefficiency or even mechanical failure.

In contrast, using a solid cover might completely restrict airflow, which is not suitable for ventilation systems that require a certain amount of air exchange. A vent that opens only in summer would not allow for appropriate ventilation during the rest of the year. As for filters, while they can be beneficial in cleaning air, they are typically used within the HVAC system rather than as a direct installation on the intake or exhaust openings. Therefore, installing a screen addresses both air quality and structural integrity effectively, making it the best choice.