If a property does not have the proper drainage system, the result can be severe flooding of the yard, basement, and even the garage. Because soil particles come in a variety of sizes, soil permeability can vary. For example, soils with small particles are called non-cohesion soils. In addition, there are soils with large particles such as gravel and sand. If you are having problems with your basement or garage flooding, you may need a specific type of drain called a sand trap drain.
Structures built on non-cohesion soils can eventually suffer severe structural damage from flooding, resulting in costly repair work. These drains are designed for soils with low permeability. Permeability is the property of the soil pore system that allows water to flow. Regarding permeability, the general rule is that the smaller the particle size, the lower the permeability of the soils. A sand drain is a hole drilled in a sand-filled, cohesive soil. Because sand has larger particles, its permeability is much higher; therefore, the water will flow through it much more easily, allowing it to drain properly.
The following is a general guide on how to install a sand trap drain:
1. When installing this drain, the height of the concrete base above the floor should be approximately 5 to 6 inches. It is important to ensure that you have adequate height above the floor before beginning the project.
2. Once you have accurate height measurements, at the location where you are installing the drain, draw a pencil line around the perimeter of the area. Use a utility knife to cut the lines in the drywall. Once you’ve cut, scoop out the bottom pieces.
3. The underside of the drywall needs to be replaced with plywood. About 2 to 3 inches of drywall should be enough. Install the plywood. Any drain pipe will need to be secured above the drain pipe that will go to the side of the sand trap. In addition, the pipe going to the sand trap must be secured a minimum of six inches above the bottom of the trap. An elbow piece should be placed in the sand trap drain to help carry the water through the drain system and move the water away from the flood prone area. Remember, a 2-inch vent is required for the sand trap.
4. Install the sand trap drain and build channels 4 to 6 inches wide on each side that slope toward the trap.
Heavy rain and melting snow can cause excess water to build up if you don’t have proper drainage. If you are a homeowner with excessive water accumulation, a sand trap drain may be the solution. If the drain for the sand trap is for the garage, a metal grate secured over the drain will allow people to walk over or over the trap without causing damage. Many experts recommend building a custom sand trap drain; however, you can purchase them as pre-made sand trap drains.
