Silt Fence Calculator
Estimate silt-fence fabric rolls, support stakes, installation trench volume and material cost from run length, roll overlap, stake spacing and waste.
Default project preview
6 rolls
Effective roll length
97 ft
Order length
561.6 ft
Purchased fabric
600 ft
Support stakes
90
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Total fence run length
Enter this project assumption in ft. The current imperial default is 520 ft.
Separate fence runs
Enter this project assumption in a unitless value. The current imperial default is 3. Minimum: 1.
Fabric roll length
Enter this project assumption in ft. The current imperial default is 100 ft.
Overlap at roll joints
Enter this project assumption in ft. The current imperial default is 3 ft. Minimum: 0.
Stake spacing
Enter this project assumption in ft. The current imperial default is 6 ft.
Anchor trench width
Enter this project assumption in in. The current imperial default is 6 in. Minimum: 0.
Anchor trench depth
Enter this project assumption in in. The current imperial default is 6 in. Minimum: 0.
Damage and layout allowance
Enter this project assumption in %. The current imperial default is 8 %. Minimum: 0. Maximum: 50.
Price per fabric roll
Enter this project assumption in a unitless value. The current imperial default is 58. Minimum: 0.
Price per stake
Enter this project assumption in a unitless value. The current imperial default is 2.2. Minimum: 0.
How to read the outputs
Effective roll length
after joint overlap. Default preview: 97 ft.
Order length
includes damage and layout allowance. Default preview: 561.6 ft.
Purchased fabric
full rolls. Default preview: 600 ft.
Support stakes
30 per average run × 3 runs. Default preview: 90.
Anchor trench volume
entered width × depth × run length. Default preview: 130 ft³.
Material cost
fabric rolls and stakes. Default preview: $546.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Effective roll length equals roll length minus joint overlap. Fabric is rounded up after a waste allowance; stakes use run length and spacing, with one additional end stake per separate run.
Related tools
Continue planning the project
FAQ
Silt Fence Calculator questions
Should silt fence cross a drainage channel?+
Silt fence is generally intended for sheet flow, not concentrated flow. Follow the approved site detail.
Why count separate runs?+
Each run needs terminal support, so several runs use more stakes than one continuous line.
Does the trench volume represent disposal?+
No. The excavated soil is commonly used to anchor and backfill the fabric according to the installation detail.