The Disadvantages of Plastic Waste Pipes

a drainpipe image by alri from

In most areas of the country, PVC, copper and cast-iron pipes are all acceptable for wastewater applications. Although PVC is considerably cheaper than the other two choices, there are some places where the use of copper or cast iron is preferred.

PVC is much more prevalent in remodelling projects and lower-end new construction, though it can be harder to properly install.

Disadvantages of ABS pipe

Acrylonitrile butadiene styrene (ABS) pipes are used in several wastewater applications. Although they work well in some plumbing lines and washing machine drains, they have poor solvent and fatigue resistance, produce large amounts of smoke if they catch fire and are apt to lose integrity due to chemical reactions with several organic materials and oxidising acids. ABS pipes can handle direct pressure from earth or slab concrete as long as they have been laid correctly. If they are not laid correctly or are exposed to high temperatures, they may lose structural integrity.

Disadvantages of PVC pipe

Polyvinyl chloride (PVC) pipe has one glaring fault when it comes to wastewater applications--it cannot be used with hot water. PVC starts to lose strength at temperatures as low as 73°F. PVC softens at 250°F and will begin to burn at 425°F. This makes the pipe very dangerous to use in areas near furnaces, ovens and other areas that are exposed to high heat. It is also degraded by most polar aromatic hydrocarbons. PVC pipe also is not a good sound insulator. Liquid running through a pipe that runs inside of a wall, ceiling or floor may be heard in the absence of background noise.

Ease of Use

Although plastic pipes are far cheaper than their cast-iron counterparts, plumbers often chose to use cast iron so the builders can't ruin the installation of the pipe close to the foundation. Plastic pipes use 250% more supports than cast iron, and the supports must be placed more carefully. Because of this, plastic piping takes twice as long to install.


When making a choice for wastewater application, some consumers would rather go with the traditional cast-iron or copper piping purely for the aesthetics. White PVC pipe is widely shunned due to its tendency to show dirt and because the purple glue that is used in its fittings often runs, streaking the outside. Black ABS pipes, although not as strong as PVC, often are chosen because they "look" better than the white pipes.