Hood Static Pressure Calculator
Total static for a hood exhaust system.
Enter your values
ⓘ Live results
Results
- Total static pressure
- 1 in wc
- Duct portion
- 0.15 in wc
- Filter portion
- 0.6 in wc
- Select fan at
- 1.15 in wc
- In Pa
- 249
Quick answer
Hood system static pressure is the sum of filter loss, duct friction and discharge loss.
TSP = filter + duct + fitting + discharge losses
How to use the Hood Static Pressure Calculator
- 1Get the filter loss from the hood submittal at design airflow.
- 2Add duct friction from length plus fitting equivalent length.
- 3Select the fan at 10-15% above the calculated total.
Worked example
Using the values the calculator loads with:
Inputs
- Filter loss0.6 in wc
- Duct length40 ft
- Friction rate0.15 in wc/100 ft
- Fitting equivalent length60 ft
- Discharge loss0.25 in wc
Results
- Total static pressure1 in wc
- Duct portion0.15 in wc
- Filter portion0.6 in wc
- Select fan at1.15 in wc
- In Pa249
Frequently asked questions
Why add a margin?
Grease build-up raises resistance over time; the margin keeps capture velocity as the system loads.
Typical total?
Most commercial hood systems land between 1.0 and 1.75 in wc.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.