Dish Room Exhaust Calculator
Exhaust airflow for a commercial dish washing room.
Enter your values
Enter the dish machine hood exhaust in CFM.
Enter the dish room area in sq ft.
Enter the general exhaust rate in CFM/sq ft.
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.
- Total exhaust
- 660 CFM
- Dish machine hood
- 300 CFM
- General room exhaust
- 360 CFM
- Makeup air
- 561 CFM (tempered in cold climates)
Quick answer
Commercial dish rooms typically need 200-500 CFM of dish-machine hood exhaust plus general room exhaust of about 1-1.5 CFM per square foot for humidity control.
Total CFM = dish machine hood CFM + area x general rate
At a glance
| What it does | Exhaust airflow for a commercial dish washing room. |
|---|---|
| Category | HVAC & Airflow |
| Inputs needed | Dish machine hood exhaust, Dish room area, General exhaust rate |
| Main output | Total exhaust |
| Formula | Total CFM = dish machine hood CFM + area x general rate |
| Cost | Free — no sign-up, no download |
How to use the Dish Room Exhaust Calculator
- 1Get the dish machine's rated hood exhaust from its data plate or spec sheet.
- 2Add general room exhaust based on floor area for humidity control.
- 3Sum both and provide matching tempered makeup air.
Inputs explained
- Dish machine hood exhaust(CFM)
- Enter the dish machine hood exhaust in CFM.
- Dish room area(sq ft)
- Enter the dish room area in sq ft.
- General exhaust rate(CFM/sq ft)
- Enter the general exhaust rate in CFM/sq ft.
Worked example
Using the values the calculator loads with:
Inputs
- Dish machine hood exhaust300 CFM
- Dish room area300 sq ft
- General exhaust rate1.2 CFM/sq ft
Results
- Total exhaust660 CFM
- Dish machine hood300 CFM
- General room exhaust360 CFM
- Makeup air561 CFM (tempered in cold climates)
Frequently asked questions
Why is humidity control important here?
Excess steam condenses on ceilings and walls, promoting mould and slip hazards without adequate exhaust.
Does the dish machine hood need grease-rated duct?
Usually a Type II (moisture/heat) hood and duct suffice unless there is significant grease-laden vapour present.
What do I need to enter into the Dish Room Exhaust Calculator?
Just 3 values: dish machine hood exhaust, dish room area, general exhaust rate. 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 Dish Room Exhaust Calculator work out the answer?
Commercial dish rooms typically need 200-500 CFM of dish-machine hood exhaust plus general room exhaust of about 1-1.5 CFM per square foot for humidity control. It applies the formula Total CFM = dish machine hood CFM + area x general rate and shows the working so you can check each step by hand.
Is the Dish Room Exhaust 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.