Sidewalls cover the perimeter minus doors. Perimeter minus openings is the linear feet; dividing by panel length gives panels.
A 20x30 tent with two 6 ft doors needs 88 ft, 9 panels.
The example
Three tents with different sizes and openings.
| A | B | C | D | E | F | G | |
|---|---|---|---|---|---|---|---|
| 1 | Case | Length | Width | Openings | Opening ft | Sidewall ft | Panels |
| 2 | 20x30 | 30 | 20 | 2 | 6 | 88 | 9 |
| 3 | 20x20 | 20 | 20 | 1 | 6 | 74 | 8 |
| 4 | 30x60 | 60 | 30 | 3 | 10 | 150 | 15 |
The formula
Perimeter, subtract openings, then divide by panel length:
How it works
Here is the logic, one piece at a time:
2*(B2+C2)is perimeter.D2*E2is door width.- The difference is sidewall feet.
- Dividing by 10 and
ROUNDUPgives panels.
Panel length is usually 10 feet; change if different.
Try it: interactive demo
Enter length, width, openings and opening width.
Variations
Window panels
Use panel length 7 ft.
Extra
Add a spare panel.
Pitfalls & errors
Check that the opening width matches your door frames.
Do not forget the 2 on perimeter.
Carry a spare panel.
Practice workbook
Frequently asked questions
Why 10?
Pole tents?
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