French drain uses 4 inch perforated pipe surrounded by 3/4 inch crushed stone. Slope minimum 1 inch per 8 feet. Wrap gravel in landscape fabric to prevent soil clogging. Use solid pipe for carrying water away from collection area.
Quick Tips
- Always order 10-15% extra materials for waste
- Check local building codes before starting
- Measure twice, cut once — verify all inputs
Frequently Asked Questions
Minimum 1 inch drop per 8 feet. Ideal 1 inch per 4 feet for better flow.
Perforated for collecting water from soil, solid for carrying water away to outlet.
Use 3/4 inch crushed stone. Provides best water flow around pipe.