If the free area of a wood louver is unknown, what free area should be assumed?

In situations where the free area of a wood louver is unknown, assuming a free area of 20%-25% is consistent with industry standards for ventilation design. This range reflects a realistic estimate for the effectiveness of louvers to allow air passage while considering factors such as the material, design, and potential obstructions.

When determining ventilation needs, it is crucial to account for the free area as it directly impacts airflow and system efficiency. A lower or higher estimate may not accurately represent the operational characteristics of the louver, potentially leading to imbalanced airflow or inadequate ventilation. Thus, the assumption of 20%-25% provides a practical and commonly accepted basis for calculations until specific measurements can be obtained.