Kitchen Exhaust Makeup Air Balance Calculator
Balance kitchen exhaust against makeup air supply.
Enter your values
Enter the total hood exhaust in CFM.
Enter the dedicated makeup air in CFM.
Enter the transfer air from dining in CFM.
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.
- Net pressure balance
- 300 CFM negative
- Percent of exhaust unmet
- 10%
- Recommended range
- 5-10% negative
- Suggested makeup air
- 2,760 CFM
Quick answer
A kitchen should run slightly negative to the dining room but not so negative that doors are hard to open or the hood loses capture.
Net = exhaust - (makeup + transfer air)
At a glance
| What it does | Balance kitchen exhaust against makeup air supply. |
|---|---|
| Category | HVAC & Airflow |
| Inputs needed | Total hood exhaust, Dedicated makeup air, Transfer air from dining |
| Main output | Net pressure balance |
| Formula | Net = exhaust - (makeup + transfer air) |
| Cost | Free — no sign-up, no download |
How to use the Kitchen Exhaust Makeup Air Balance Calculator
- 1Enter total hood exhaust from all hood sections.
- 2Enter dedicated makeup air unit output.
- 3Enter any transfer air pulled in from the dining room, then check the balance is 5-10% negative.
Inputs explained
- Total hood exhaust(CFM)
- Enter the total hood exhaust in CFM.
- Dedicated makeup air(CFM)
- Enter the dedicated makeup air in CFM.
- Transfer air from dining(CFM)
- Enter the transfer air from dining in CFM.
Worked example
Using the values the calculator loads with:
Inputs
- Total hood exhaust3000 CFM
- Dedicated makeup air2400 CFM
- Transfer air from dining300 CFM
Results
- Net pressure balance300 CFM negative
- Percent of exhaust unmet10%
- Recommended range5-10% negative
- Suggested makeup air2,760 CFM
Frequently asked questions
What if the kitchen is too negative?
Doors become hard to open, outside air infiltrates uncontrolled, and the hood can lose capture — add more makeup air.
What if it's positive?
Grease-laden air can spill into the dining room; increase exhaust or reduce makeup air.
What do I need to enter into the Kitchen Exhaust Makeup Air Balance Calculator?
Just 3 values: total hood exhaust, dedicated makeup air, transfer air from dining. 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 Kitchen Exhaust Makeup Air Balance Calculator work out the answer?
A kitchen should run slightly negative to the dining room but not so negative that doors are hard to open or the hood loses capture. It applies the formula Net = exhaust - (makeup + transfer air) and shows the working so you can check each step by hand.
Is the Kitchen Exhaust Makeup Air Balance 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.