Home Inspection State Practice Exam

A newly built ventilated crawl space with a vapor retarder must have how much net ventilation opening per 1,500 square feet?

1. 1 square foot

2. 2 square feet

3. 3 square feet

4. 4 square feet

The correct answer is: 1 square foot

In a newly built ventilated crawl space, the standard requirement for net ventilation opening is typically 1 square foot for every 1,500 square feet of crawl space area. This guideline is established to ensure adequate airflow, which helps control humidity levels and prevent moisture-related issues that can lead to problems such as mold growth and wood rot. The purpose of the vapor retarder combined with proper ventilation is to reduce the amount of moisture that enters the crawl space from the ground and to manage the moisture in the air. The specified amount of net ventilation ensures an appropriate exchange of air, maintaining a healthy environment within the crawl space. This requirement is part of the building code guidelines meant to protect the integrity of the building structure and the health of its occupants. Proper ventilation is crucial in maintaining overall building performance, especially in areas known for high moisture levels.