Drainage Materials
Drainage Materials Rip Rap
Rip rap is big, angular broken stone placed along creek banks, ponds, and drainage channels to stop water from cutting into the ground. Pieces run anywhere from a few inches to more than a foot across, and each stone is heavy enough that a strong current can't roll it away. The rock is quarried and broken to size, so the sharp faces wedge into each other and lock in place.
You'll see rip rap sold by class. State DOTs in the Northeast use R-3 through R-8, and the USACE spec uses Class I through Class IV. The number tells you the size range and the average stone weight. A small R-3 might fit in one hand while an R-7 takes a loader to move. Placed rip rap weighs about 1.4 tons per cubic yard, and the bigger classes cost more per ton because they take more work to quarry and place.
Compare every grade
| Grade | Size | Shape | Washed | Top use | We deliver |
|---|---|---|---|---|---|
| Rip Rap (Class 2) | Class 2 | — | — | Erosion control | Reference only |
| Rip Rap (Class 3) | Class 3 | — | — | Erosion control | Reference only |
| Rip Rap (Class3) | Class3 | — | — | Erosion control | Reference only |
What people use it for
How to choose within drainage materials rip rap
French drain
Washed 3/4" to 1" stone. Angular so it locks around the pipe, washed so it doesn't clog with fines.
Foundation perimeter
Larger clean stone — river rock or #57 — moves water away without holding it.
Downspout dispersion
Cover the splash zone with clean rock so runoff spreads instead of digging a hole.
Other drainage materials families
Drainage Materials Drain Rock
ReferenceDrain rock is washed, clean stone with the fines rinsed out and the pieces sized close to the same.
Drainage Materials Sand
ReferenceDrainage sand is a clean, washed sand with the fines rinsed out so water moves through it instead of pooling.
Drainage Materials Bedding
ReferenceDrainage bedding is clean, angular crushed stone that you place under and around a pipe in a trench.
Drainage Materials Fill Material
ReferenceAny stone sold as drainage fill has been washed and screened so no dust or sand rides along with it.
Septic Rock
ReferenceSeptic rock is clean, washed stone that surrounds the perforated pipes in a septic drain field.