Drainage Calculator

Calculate French drain materials β€” perforated pipe, drainage gravel, landscape fabric, and catch basins by trench dimensions.

πŸ’§ Drainage Calculator

Results

Gravel Fill2.8 cu yd
Perforated Pipe50.00 ft
Landscape Fabric300.00 sq ft
Fabric Rolls1.0 rolls
Catch Basins1 basins

πŸ’‘ How to Calculate French Drain Materials

A French drain consists of a gravel-filled trench with a perforated pipe at the bottom, wrapped in landscape fabric to prevent soil migration. Standard residential dimensions: 12 inches wide Γ— 18 inches deep. The trench should slope ΒΌ inch per foot minimum toward the outlet.

Materials breakdown: the pipe runs the full trench length, gravel fills the entire trench volume, and landscape fabric wraps around the gravel (bottom, sides, and top overlap). Catch basins are placed every 50 feet or at corners to provide inspection and cleanout points.

A 50 ft French drain, 12" wide Γ— 18" deep: gravel = 2.8 cu yd, pipe = 50 ft, landscape fabric = 200 sq ft, 1 catch basin. Total material cost: $200–$400.

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