Poultry Barn Ventilation Calculator
Minimum and tunnel ventilation CFM for a poultry house.
Enter your values
Enter the number of birds you are working with.
Enter the average bird weight in lb.
Enter the peak cfm per lb in CFM/lb.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Peak tunnel ventilation
- 495,000 CFM
- Total live weight
- 90,000 lb
- Fans at 25,000 CFM each
- 20
- Minimum winter ventilation (5% of peak)
- 24,750 CFM
Quick answer
Poultry housing tunnel ventilation is commonly sized around 5-6 CFM per pound of live bird weight at peak summer heat.
CFM = birds x avg weight x CFM per lb
At a glance
| What it does | Minimum and tunnel ventilation CFM for a poultry house. |
|---|---|
| Category | HVAC & Airflow |
| Inputs needed | Number of birds, Average bird weight, Peak CFM per lb |
| Main output | Peak tunnel ventilation |
| Formula | CFM = birds x avg weight x CFM per lb |
| Cost | Free — no sign-up, no download |
How to use the Poultry Barn Ventilation Calculator
- 1Enter the flock size and average bird weight for the growth stage.
- 2Apply a peak CFM-per-pound rate — around 5-6 for broilers in hot weather.
- 3Scale minimum winter ventilation down to roughly 5% of the peak figure for air quality only.
Inputs explained
- Number of birds
- Enter the number of birds you are working with.
- Average bird weight(lb)
- Enter the average bird weight in lb.
- Peak CFM per lb(CFM/lb)
- Enter the peak cfm per lb in CFM/lb.
Worked example
Using the values the calculator loads with:
Inputs
- Number of birds20000
- Average bird weight4.5 lb
- Peak CFM per lb5.5 CFM/lb
Results
- Peak tunnel ventilation495,000 CFM
- Total live weight90,000 lb
- Fans at 25,000 CFM each20
- Minimum winter ventilation (5% of peak)24,750 CFM
Frequently asked questions
Why does ventilation change so much winter to summer?
Winter ventilation only needs to remove moisture and gases; summer tunnel ventilation must also cool the birds by wind-chill.
Tunnel speed target?
Tunnel-ventilated houses commonly target 350-500 FPM air speed down the house length in summer.
What do I need to enter into the Poultry Barn Ventilation Calculator?
Just 3 values: number of birds, average bird weight, peak cfm per lb. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Poultry Barn Ventilation Calculator work out the answer?
Poultry housing tunnel ventilation is commonly sized around 5-6 CFM per pound of live bird weight at peak summer heat. It applies the formula CFM = birds x avg weight x CFM per lb and shows the working so you can check each step by hand.
Is the Poultry Barn Ventilation Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.