How to Calculate Eave Ventilation Area
- 1). Divide your attic into square sections and measure each section's width and length with a measuring tape.
- 2). Multiply the individual sections' width by their length and add the figures together to determine the total area.
- 3). Divide this area by 300. The ratio of ventilation-to-attic space must be at least 300:1. Divide the result by 2. The answer is the required square feet of eave ventilation.
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