Estimate soffit materials for your roof overhang project. Enter the perimeter and overhang depth to calculate the number of soffit panels, J-channel, and vented panels needed for proper attic ventilation.
Enter Your Measurements
Results
Soffit Area
240
sq ft
Total Panels
132
panels
Vented Panels
66
panels
Solid Panels
66
panels
J-Channel
27
pieces (12 ft)
F-Channel
14
pieces (12 ft)
Formula
How to Use This Calculator
How to Use
- 1
Measure the total perimeter of the house where soffit will be installed.
- 2
Measure the overhang depth from the wall to the fascia in inches.
- 3
Decide what percentage of soffit panels should be vented (50% is typical for adequate attic ventilation).
Frequently Asked Questions
Frequently Asked Questions
Should all soffit be vented?
What is the difference between soffit and fascia?
How wide is standard soffit?
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About This Calculator
This calculator uses the formula: Soffit Area = Perimeter × Overhang Depth ÷ 12 | Panels = Area ÷ Panel Coverage × 1.1. All calculations follow industry-standard methods. Results are estimates — always verify with a licensed professional for structural or code-compliant work.
Built and maintained by the CalcSmart team. Last updated March 2026.
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