Bay Area Home Inspection

Today the drain/waste pipe installed under your house is mostly ABS pipe (Acrylonitrile Butadiene Styrene). ABS piping systems is a black rigid, non-pressurized plastic pipe used to drain your sinks, tubs, showers, toilet and washing machines. It is also used to vent the drain and waste pipes.

Plastic straps with a rigid hanger are used to support the ABS pipes off the ground and carry the water weight. As the strapping material ages, it weakens. Once this occurs, it's common to find broken strapping throughout the DWV system (drain, waste, ventilation). As each section of strapping breaks, more weight is transferred to other sections, resulting in more broken straps.

An earthquake can cause drain pipe sections to fall.

Sometimes when a strap breaks, the pipes leak waste water at the fittings (where pipe sections are joined together). In the photo, this homeowner was lucky there wasn't any leakage. Most people never look under their house. A fallen drain pipe can leak for years before being discovered.

A badly leaking drain/waste pipe can create an unhealthy environment in your crawlspace with smells permeating the house. An Antioch house inspector snapped the photo.