Alabama Contractors License Practice Exam

Which of the following is a characteristic of damp proofing?

1. Stops all moisture

2. Allows moisture vapor to escape

3. Requires no maintenance

4. Applied in a single coat

The correct answer is: Allows moisture vapor to escape

The characteristic of damp proofing that allows moisture vapor to escape is essential for the longevity and effectiveness of a structure. Damp proofing is designed to limit the passage of moisture in liquid form but does not completely seal off vapor. This ability to allow vapor to escape helps prevent the buildup of pressure, which could lead to damage within the walls or foundation over time. It is critical in environments where moisture is present but needs to be managed rather than entirely blocked. By permitting moisture vapor to escape, damp proofing contributes to maintaining the structural integrity and reducing conditions that could promote mold and decay. The other characteristics mentioned do not accurately describe damp proofing. For instance, while damp proofing significantly reduces moisture intrusion, it may not fully stop all moisture, particularly under severe conditions. Additionally, while damp proofing materials may require less frequent maintenance than other methods, they still may need inspections and potential touch-ups over time. Lastly, damp proofing applications can vary, as thickness and the method of application (single coat versus multiple coats) depend on the product used and the specific building requirements. Hence, the correct answer highlights an essential functional aspect of damp proofing that optimally balances moisture control with structural health.