CFM Calculator for 500 Sq Ft Room
Find the exact CFM airflow needed for a 500 square foot room. Get recommended duct sizes, BTU load estimates, and HVAC sizing data for 500 sqft spaces.
Airflow Requirements for 500 Square Feet
Required CFM
500
Est. BTU Load
12,500
Cooling Tons
1.04
Duct Size
12"
A 500 square foot room requires approximately 500 CFM of airflow for proper heating and cooling. This is based on the industry standard rule of 1 CFM per square foot. The estimated cooling load is 12,500 BTU (1.04 tons), and the recommended round duct size is 12 inches at a quiet velocity of 700 FPM.
How We Calculated This
Step 1: CFM Requirement
CFM = 500 sqft × 1 CFM/sqft = 500 CFM Step 2: BTU Load Estimate
BTU = 500 sqft × 25 BTU/sqft = 12,500 BTU Using 25 BTU per square foot as a general residential estimate. Actual load depends on insulation, climate, and sun exposure.
Step 3: Duct Size
Diameter = √(4 × 500 ÷ (π × 700)) × 12 ≈ 12 inches Based on 700 FPM velocity for quiet residential operation.