Key takeaways
- A common guideline is about 6 inches of fall in the first 10 feet from the house
- Drains and swales need steady, continuous slope
- Very steep flows cause erosion
- Always check what the water does at the bottom
Away from the foundation
Building codes and common guidelines call for the ground to slope away from the foundation, often cited as about six inches of fall over the first ten feet where the lot allows. This is about five percent.
Swales
Grassed swales commonly run at slopes between about one and several percent. Too flat, and water sits. Too steep, and it scours. Rock lining allows steeper runs.
Pipes
Drain pipes commonly need about one percent fall, roughly one inch per ten feet, as a minimum. Steeper is fine for solid pipe. Perforated lines work best with a consistent slope.
Hard surfaces
Paving should slope away from structures, commonly around one to two percent at least, with channel drains where it cannot.
Verify, do not guess
A laser or builder’s level shows what your ground is really doing. The eye is a poor judge of slope.
Quick answers
How can I check my slope?
Stretch a string level from the house outward and measure the drop, or ask us for a free slope check.
Is more slope always better?
No. Too much creates erosion and fast runoff problems downhill.
Want a professional opinion on your property?
We offer a free visit and a clear written plan. Call (615) 393-6985 or use the form below.
