Piping Options

Millions of piping systems across North America bring clean water to families, schoolchildren, doctors/patients, and workers. They also carry away sewage and other waste, among other essential functions.

Materials play a significant role in how such systems perform. As communities initiate historic investments in piping infrastructure, they must ensure health and safety while addressing sustainability and environmental concerns. Here are key factors for each of the main types of piping.

Piping Materials

Copper has been used for centuries in plumbing and is valued for its proven resilience and non-toxic composition. Safety of copper and brass pipe and fittings is ensured by the Lead and Copper Rule to prevent leaching of harmful lead particles into piping systems. 

Key applications: Water service lines, hot & cold water distribution, (steam/water) heating

Benefits: high recycled content, non-combustible, resilient to chemicals, impermeable, repairable, no leaching concerns, 75-year product life, recycled at end of life

Drawbacks: heavier weight, higher material, and installation cost

Cast iron is considered one of the most robust and forgiving materials for wastewater and sewer, selected for use in thousands of commercial and residential structures because of its safety and performance.

Key applications: Wastewater drain lines, soil pipe/sewer lines, (steam/water) heating

Benefits: high recycled content, structural strength, good for below-ground applications, resilient to chemicals, non-combustible, impermeable, no leaching concerns, 100-year product life, recycled at end of life

Drawbacks: heavier weight, higher material cost

Lead pipes were widely used for decades, but create serious health hazards due to the leaching of lead particles into water. 

Well-known incidents in Flint MI, Newark NJ, and elsewhere have made it imperative to replace these unsafe pipes, work that continues in hundreds of communities.

Key applications: Water service lines, hot & cold water distribution, (steam/water) heating

Benefits: None (outweighed by risks)

Drawbacks: toxic leaching of lead into water, heavier weight

Like iron, steel is valued for its structural strength and proven performance. Steel pipes offer a high level of protection in fire incidents due to their non-combustible nature.

Key applications: Sprinkler systems, electrical conduits

Benefits: high recycled content, non-combustible, resilient to chemicals, repairable, long product life, recycled at end of life

Drawbacks: heavier weight, higher material, and installation cost

PVC Pipes: Since the 1980s, pipes made of polyvinyl chloride have become a widely used material for water and drain-waste-vent (DWV) systems. PVC is considered a “Red List” material, and advantages in cost and corrosion resistance must be balanced by questions about pipe resilience, toxic production processes, and linear product lifecycle (generally not recycled).

Key applications: Water distribution, sewer, DWV, conduit

Benefits: Low cost, lightweight, resistant to corrosion

Drawbacks: Susceptible to cracking, deformation, or degradation when exposed to incompatible chemicals, temperature extremes, or mechanical stresses; can leach chemicals and shed microplastics; susceptible to UV/sunlight degradation and embrittlement; combustible (produces smoke and toxic combustion byproducts); fossil-fuel-based material; contains chlorine and vinyl chloride-derived compounds; typically landfilled at end of life

PE Pipes: Pipes made of polyethylene have become widely used for water distribution, gas distribution, and underground applications from the 1950s onwards. PE pipes are flexible and corrosion resistant, but have suffered from some early failures, questions about microplastic generation, risks from chemical permeation, and environmental impacts of production and disposal.

Key applications: Water distribution, gas distribution, underground utilities

Benefits: Flexible, lightweight, resistant to corrosion

Drawbacks: Can leach chemicals and shed microplastics; permeable to certain fuels, solvents, and environmental contaminants; susceptible to damage from chemicals, UV/sunlight, excessive heat, and mechanical stresses; highly reactive to temperature differences; fossil-fuel-based material; typically landfilled at end of life

PEX Pipes: Piping made of cross-linked polyethylene have grown in use since their introduction in the early 2000s. Aggressive marketing of PEX advantages such as cost and flexibility need to be balanced by questions about interactions with potable water disinfectants affecting long-term durability, complaints about chemical leaching, and susceptibility to damage from rodents, insects, and UV light/sunlight.

Key applications: Potable water distribution, residential plumbing, radiant heating systems, hydronic heating and cooling, snow-melt systems

Benefits: Low cost, flexible, fewer fittings, resistant to corrosion, lightweight

Drawbacks: Fossil-fuel-based material, combustible (produces smoke and toxic combustion byproducts), potential chemical leaching and microplastic shedding, susceptible to degradation from chlorine and chloramine disinfectants, damaged by UV light and prolonged sunlight exposure, vulnerable to rodents and insects, difficult to recycle and typically landfilled at end of life

ABS Pipes: Pipes made of acrylonitrile butadiene styrene (ABS) have gained market share in drain-waste-vent (DWV) applications since the 1980s because they are lightweight and durable. These advantages should be considered alongside a history of product failures in some regions, concerns about combustibility, vulnerability to heat and sunlight, and a linear lifecycle.

Key applications: DWV systems, underground drainage

Benefits: Lightweight, impact resistant, performs well in cold temperatures

Drawbacks: History of product failures in some jurisdictions; susceptible to damage from chemicals, excessive heat, and UV/sunlight exposure; can leach chemicals and shed microplastics; combustible (produces smoke and toxic combustion byproducts); fossil-fuel-based material; typically landfilled at end of life

Galvanized Steel Pipes: For much of the 20th century, galvanized steel pipes were a standard choice for water distribution systems because of their strength, durability, and familiarity to contractors. While these pipes can withstand physical abuse and high pressures, they also pose internal corrosion issues and maintenance challenges in aging systems.

Key applications: Water distribution, fire protection systems, outdoor piping

Benefits: Strong, durable, impact resistant, noncombustible, performs well in exposed applications

Drawbacks: Susceptible to internal corrosion (rust) over time; can accumulate mineral deposits that restrict water flow; heavier than alternatives; vulnerable to galvanic corrosion when connected to dissimilar metals

Pipe System Applications

Plumbing designed to move wastewater, sewage, and associated gases out of a building. DWV systems include physical drain mechanisms, piping, traps, and fittings throughout the structure, as well as sewer lines that return waste back to a municipal or septic system for treatment.

Vent pipes complement drain/waste systems by allowing mixtures of liquid and solid waste to flow easily down pipes while preventing siphonage and backflows. Vents also carry away gases and fumes associated with waste, allowing them to pass out of a structure to safeguard interior air quality.

Sprinkler systems protect occupant safety and limit property damage during structural fires. Fire-sprinkler systems can deliver water for suppression of flames, usually controlled by sensors in the protected space.

The main types of systems – wet, dry, preaction, and deluge – vary in how they are triggered, but are generally similar in construction, featuring a network of pipes and control valves located in the ceiling plenum, with sprinkler heads and sensors located below the ceiling plane.

 

Potable systems supply water for drinking, washing, sanitary use, and appliances. One of the most critical parts of these systems are the pipes that connect buildings to community water sources, whether private systems or municipal supplies. Water systems then distribute water throughout a structure via a system of vertical “riser” pipes that pass from floor to floor in a structure and horizontal runs that connect individual fixtures to the water supply. 

Water heaters and storage tanks are also a part of this system, as are control valves, faucets, and other fixtures.

There are many additional types of pipe systems in buildings, including electrical conduit, heating and/or cooling systems, medical gas distribution systems, and others. We do not focus on these systems today, but may add them in the future.

Additional Resources

Health & Research

  • Healthy Building Network: analysis of chemicals, polymers, metals, and other substances used in construction more >
  • Healthy Materials Lab: resources for designers and architects to eliminate toxic materials in the built environment more >
  • Center for Plumbing Safety: Collaborative of microbiologists, risk assessors, data scientists, engineers, ecologists, and political scientists researching issues related to pipe and plumbing systems more >