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 instance, soils with small particles are called cohesionless soils. As well, there is soil with large particles such as gravel and sand. If you have problems with flooding of your basement or garage, you may need a specific type of drain called a sand trap drain.
Structures built on cohesionless soils can eventually undergo severe structural damage from flooding which will result in a costly repair job. These drains are designed for soils with low permeability. Permeability is the property of the soil pore system that allows water to flow. When it comes to permeability, the general rule of thumb is the smaller the particle size, the lower the permeability of the soils. A sand drain is a hole drilled in a cohesive soil and filled with sand. Because the sand has bigger particles, its permeability is much higher; therefore 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 foundation above the floor should be about 5- 6 inches. It is important to make sure you have adequate height above the floor before you begin the project.
2. Once you have the accurate height measurements, at the spot where you are installing the drain, make a line with a pencil around the area’s perimeter. Use a utility knife to cut through the lines on the drywall. Once you have cut through take out the pieces at the bottom.
3. The bottom of the drywall needs to be replaced with plywood. About 2 or 3 inches of the drywall should sufficient. Install the plywood. Any drain pipes will have to be secured above the drain pipe that will be going into the side of the sand trap. As well, the pipe going into the sand trap should be secured a minimum of six inches above the bottom of the trap. An elbow piece has to be attached to the sand trap drain in order to help transport the water through the drain system and carry the water 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 construct troughs that are about 4 to 6 inches wide on each side that slant into the trap.
Extensive rain and melting snow can cause excessive water to accumulate if you do not have proper drainage. If you are a homeowner with excess water accumulation, 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 permit people to walk or drive over the trap without causing damage. Many experts recommend building a custom sand trap drain; however you can buy them as pre-made sand trap drains.