Raised Floor Tile Airflow Calculator
Perforated tile count for a rack row.
Enter your values
Enter the row airflow required in CFM.
Choose one of: 25% open, 40% open, Grate 56% open.
Enter the plenum pressure in in wc.
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.
- Airflow per tile
- 402 CFM
- Tiles required
- 15
- Row airflow
- 6,000 CFM
- Plenum pressure
- 0.05 in wc
- Note
- Keep plenum clear — cable congestion kills tile flow
Quick answer
Each perforated floor tile passes airflow set by its open area and the under-floor pressure, typically 300-600 CFM.
tiles = rack airflow / CFM per tile
At a glance
| What it does | Perforated tile count for a rack row. |
|---|---|
| Category | HVAC & Airflow |
| Inputs needed | Row airflow required, Tile type, Plenum pressure |
| Main output | Airflow per tile |
| Formula | tiles = rack airflow / CFM per tile |
| Cost | Free — no sign-up, no download |
How to use the Raised Floor Tile Airflow Calculator
- 1Total the airflow the rack row needs.
- 2Pick the tile type installed in the cold aisle.
- 3Measure actual plenum pressure — cable trays under the floor often halve theoretical flow.
Inputs explained
- Row airflow required(CFM)
- Enter the row airflow required in CFM.
- Tile type
- Choose one of: 25% open, 40% open, Grate 56% open.
- Plenum pressure(in wc)
- Enter the plenum pressure in in wc.
Worked example
Using the values the calculator loads with:
Inputs
- Row airflow required6000 CFM
- Tile type25% open
- Plenum pressure0.05 in wc
Results
- Airflow per tile402 CFM
- Tiles required15
- Row airflow6,000 CFM
- Plenum pressure0.05 in wc
- NoteKeep plenum clear — cable congestion kills tile flow
Frequently asked questions
Can I just add more tiles?
Only up to a point — too many tiles drops plenum pressure and starves the far end of the row.
Blanking panels?
Essential — open rack U-space lets hot air recirculate straight back to the intakes.
What do I need to enter into the Raised Floor Tile Airflow Calculator?
Just 3 values: row airflow required, tile type, plenum pressure. 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 Raised Floor Tile Airflow Calculator work out the answer?
Each perforated floor tile passes airflow set by its open area and the under-floor pressure, typically 300-600 CFM. It applies the formula tiles = rack airflow / CFM per tile and shows the working so you can check each step by hand.
Is the Raised Floor Tile Airflow 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.