Certified Energy Auditor Practice Exam

What type of moisture entry involves the movement of liquid water through porous materials?

1. Air leakage

2. Vapor diffusion

3. Bulk moisture

4. Absorption

The correct answer is: Bulk moisture

The process of moisture entry through the movement of liquid water through porous materials is known as bulk moisture transport. This occurs when water is present in a significant volume and moves through materials like concrete, brick, or other porous substrates. Unlike vapor diffusion, which involves the movement of water vapor molecules through air or across materials, bulk moisture is more concerned with the actual liquid water entering the porous materials due to gravity, hydrostatic pressure, or capillary action. Understanding bulk moisture is vital for assessing building integrity and durability, especially in terms of preventing water-related issues such as mold growth, structural damage, or degradation of building materials. Recognizing the importance of this entry mechanism helps energy auditors identify potential problem areas in a building and take appropriate steps to mitigate moisture-related risks. In contrast, air leakage involves the unintended flow of air through cracks and openings in a building envelope, vapor diffusion pertains to the movement of water vapor through materials, and absorption refers to the process where materials take in moisture directly. Each of these processes plays a role in the overall moisture dynamics in construction and energy efficiency, but when specifically referring to the movement of liquid water through porous materials, bulk moisture is the correct term.