Pipes and Subgrade Problems

Subgrade Moisture Problems

• Naturally occurring surface water results from rainfall and snow melt. Ideally, water runs away from a home’s foundation to collect in storm sewers or drain into the soil. Improper grading or heavy soil types can impede drainage and cause water to collect against the foundation, where it can seep into basements. Groundwater exists in aquifers, or water-saturated permeable bedrock, and in water tables, which is the upper saturation point of soil, according to the U.S. Geological Survey. Heavy rainfall can raise the water table level, sometimes to the point of flooding structures.

Downspout Drainage Pipes

• As gutters collect rainwater from roofs, they channel it into downspouts. Water naturally exits downspouts around a home’s foundation unless it is directed outward. Short, flexible downspout extenders are needed to control foundation water problems in some locations, but they are often inadequate in other locations. According to Joseph Truini of This Old House, connecting downspouts to an underground network of pipes can channel rainwater runoff satisfactorily from your house. This project is a three-step process: trenching, laying pipe and backfilling the trench. Using non-perforated pipes, elbows, and T-connectors, you can design a customized underground drainage system that conforms to the lay of your land.

French Drain Pipes

• French drains are pipe-and-gravel systems that slow runoff and collect water, allowing it to drain more easily through large pieces of gravel instead of waterlogged soil. Instead of using solid pipes, such as those found in downspout drainage systems, French drains use perforated pipes. According to Tim Carter of AskTheBuilder.com, perforated pipes are laid in the bottom of gravel-lined trenches. The gravel creates a path of least resistance to water that drains more slowly in heavy soils, and the perforated pipe at the bottom of the trench collects the re-directed water and channels it away from the foundation.

Basement Plumbing Pipes

• Basement plumbing cannot rely on gravity to drain pipes or flush toilets because a home's piping system is above grade. Subgrade locations require systems that pump water and wastewater to existing overhead pipes before exiting. Home improvement TV host Bob Vila describes macerating, composting and sewage ejector systems as “upflushing toilet systems.” To minimize clogs, macerating systems reduce toilet waste to smaller, more easily flushable pieces. Composting toilets rely on ventilation for aerobic decomposition of solid waste. Toilets in sewage ejector systems sit atop mini-septic tanks, from which waste is pumped into overhead pipes for removal.