Residential Building Inspector Practice Exam

What is the minimum vent area required for a roof?

1. 1/100 of square footage

2. 1/150 of square footage

3. 1/200 of square footage

4. 1/300 of square footage

The correct answer is: 1/150 of square footage

The minimum vent area required for a roof is typically determined as 1/150 of the square footage of the attic space. This calculation is based on building codes and standard practices aimed at ensuring proper ventilation, which helps to regulate temperature and moisture levels in the attic. Adequate venting is crucial for preventing conditions like ice damming in colder climates and excessive heat buildup in warmer ones, both of which can lead to significant damage over time. By using the 1/150 ratio, it recognizes the need for proper air exchange, taking into account that each square foot of attic area needs a certain amount of vent area to allow for adequate airflow. This helps to maintain a balanced environment, promoting energy efficiency and prolonging the lifespan of roofing materials.