Construction Supervisor License Practice Exam

What is the purpose of attic ventilation in dwellings?

1. Allow drying and shrinkage of framing members

2. Prevent condensation on framing members in winter

3. Keep attics cool in summer

4. Minimize varmint / insect infestation

The correct answer is: Prevent condensation on framing members in winter

The purpose of attic ventilation in dwellings is primarily to prevent condensation on framing members during the winter months. Proper ventilation helps to equalize the temperature and humidity levels in the attic space and the living areas. When warm, moist air from the living spaces rises and enters the cooler attic space, it can lead to condensation forming on the cold surfaces, such as framing members, which can ultimately result in wood rot, mold growth, and a deterioration of structural integrity. While the other options contain elements that are relevant to the overall function of an attic, they do not address the primary purpose as directly as preventing condensation. For example, while allowing drying and shrinkage of framing members may occur through proper ventilation, it is not the main focus of why ventilation is installed. Keeping attics cool in summer is a benefit but relates more to energy efficiency and comfort rather than condensation prevention, and minimizing varmint and insect infestations is certainly a consideration with ventilation systems, but it is not the primary role. Thus, preventing condensation on framing members is key to maintaining the health of a structure throughout varying seasonal conditions.