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 cohesionless soils. In addition, there is soil 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 cohesionless 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 through. When it comes to permeability, the general rule is that the smaller the particle size, the lower the permeability of soils. A sand drain is a hole drilled in cohesive, sand-filled 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 pad above the floor should be about 5-6 inches. It’s important to make sure you have the proper height above the ground before starting the project.
2. Once you have accurate height measurements, at the location where the drain will be installed, 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, pop out the pieces at the bottom.
3. The bottom of the drywall should be replaced with plywood. About 2 to 3 inches of drywall should be enough. Install the plywood. All drain pipes will need to be secured above the drain pipe that will go to the side of the sand trap. Also, the pipe leading to the sand trap must be secured a minimum of six inches above the bottom of the trap. An elbow piece should be attached to the sand trap drain to help carry the water through the drainage system and away from the area that is prone to flooding. Remember, a 2-inch vent is required for the sand trap.
4. Install the sand trap drain and build gutters about 4 to 6 inches wide on each side that slope toward the trap.
Heavy rains and melting snow can cause excess water to collect if you don’t have proper drainage. If you own a home with excess water buildup, a sand trap drain may be the solution. If the sand trap drain is for the garage, a metal grate secured over the drain will allow people to walk or drive 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.
