The slope, depth, and gravel calculations that prevent yard pooling and basement seepage — distilled onto one page you can take to the hardware store.
1-inch drop per 8 feet of run — the golden rule for gravity-fed drainage, with real examples.
Match 4-inch vs. 6-inch pipe to your square footage of pooled water.
Exactly how much #57 stone and landscape fabric you need per linear foot.
The 3 errors that cause most DIY French drains to fail within 2 years.
Enter your email to receive the printable cheat sheet — field-tested by RHS drainage crews.