HVAC & Airflow

Kiln Ventilation CFM Calculator

Exhaust hood airflow for a pottery kiln.

Enter your values

Choose one of: Canopy hood, Downdraft vent.

Enter the hood width in ft.

Enter the hood depth in ft.

Enter the capture velocity in FPM.

Enter the kiln volume in cu 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.

Results
Required exhaust
2,000 CFM
Method
Canopy hood above the kiln
Duct size at 1200 FPM
17.5 in dia
Makeup air needed
2,000 CFM
Room air changes in a 2000 cu ft studio
60

Quick answer

Kiln canopy hoods are sized on hood face area at 100-150 FPM capture velocity, with downdraft vents rated per cubic foot of kiln.

CFM = hood area x capture velocity

At a glance

What it doesExhaust hood airflow for a pottery kiln.
CategoryHVAC & Airflow
Inputs neededMethod, Hood width, Hood depth, Capture velocity, Kiln volume
Main outputRequired exhaust
FormulaCFM = hood area x capture velocity
CostFree — no sign-up, no download

How to use the Kiln Ventilation CFM Calculator

  1. 1Decide between a canopy hood or a downdraft vent system.
  2. 2For a canopy, size it to overhang the kiln by 6-12 inches on each side.
  3. 3Provide an equal amount of makeup air so the room does not go strongly negative.

Inputs explained

Method
Choose one of: Canopy hood, Downdraft vent.
Hood width(ft)
Enter the hood width in ft.
Hood depth(ft)
Enter the hood depth in ft.
Capture velocity(FPM)
Enter the capture velocity in FPM.
Kiln volume(cu ft)
Enter the kiln volume in cu ft.

Worked example

Using the values the calculator loads with:

Inputs

  • MethodCanopy hood
  • Hood width4 ft
  • Hood depth4 ft
  • Capture velocity125 FPM
  • Kiln volume10 cu ft

Results

  • Required exhaust2,000 CFM
  • MethodCanopy hood above the kiln
  • Duct size at 1200 FPM17.5 in dia
  • Makeup air needed2,000 CFM
  • Room air changes in a 2000 cu ft studio60

Frequently asked questions

Do electric kilns need venting?

Yes — firing clay and glazes releases sulphur, fluorine and carbon monoxide regardless of the heat source.

Downdraft advantages?

It captures fumes at source with far less airflow, so you lose less conditioned air.

What do I need to enter into the Kiln Ventilation CFM Calculator?

Just 5 values: method, hood width, hood depth, capture velocity, kiln volume. 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 Kiln Ventilation CFM Calculator work out the answer?

Kiln canopy hoods are sized on hood face area at 100-150 FPM capture velocity, with downdraft vents rated per cubic foot of kiln. It applies the formula CFM = hood area x capture velocity and shows the working so you can check each step by hand.

Is the Kiln Ventilation CFM 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.