Understanding CFM Calculations
Learn how to calculate the required airflow (CFM) for proper ventilation in any space.
\[ CFM = \frac{Room Volume \times Air Changes per Hour}{60} \]
Where:
- CFM = Cubic Feet per Minute
- Room Volume = Length × Width × Height (cubic feet)
- Air Changes per Hour (ACH) = Number of complete air replacements per hour
Calculation Steps
- Measure room dimensions (length, width, height)
- Convert measurements to feet if necessary
- Calculate room volume in cubic feet
- Determine required air changes per hour (ACH)
- Apply the CFM formula
- Round the result to get required CFM
Example Calculation
Problem:
Calculate the required CFM for a room with:
- Length = 20 feet
- Width = 15 feet
- Height = 8 feet
- ACH = 6 (typical for residential spaces)
Solution:
- Calculate room volume: \[ Volume = 20 \times 15 \times 8 = 2,400 \text{ cubic feet} \]
- Apply CFM formula: \[ CFM = \frac{2,400 \times 6}{60} = 240 \text{ CFM} \]
Visual Reference