What is the proper slope for horizontal drainage piping?

The proper slope for horizontal drainage piping is typically 1/4 inch per foot. This standard allows for optimal drainage, ensuring that wastewater and solids flow easily through the pipes without risk of clogging. A slope that is too steep, such as 1/2 inch or 3/4 inch per foot, could result in solids settling out of the flow, leading to blockages. Conversely, a slope that is too shallow, like 1/8 inch per foot, may not provide sufficient force to move the waste efficiently, which can also result in drainage issues. Therefore, maintaining a slope of 1/4 inch per foot balances effective wastewater transport and minimizes the potential for stands and blockages in the drainage system.