Pipe Corrosion: Causes, Warning Signs & Repair Options

Most homeowners and building owners use potable water every day without thinking about the pipes that carry it. But when those pipes begin to corrode, the impact can be serious. Pipe corrosion can affect water quality, damage plumbing systems, create leaks, and, in some cases, contribute to the release of unwanted metals or other contaminants into drinking water.

Left untreated, corrosion can lead to expensive repairs, property damage, and even full plumbing system failure. The good news is that understanding the causes and warning signs of corrosion can help property owners take action before small issues become major problems.

This guide explains what pipe corrosion is, what causes it, how it affects plumbing systems, how to reduce the risk, and how ePIPE can help treat corrosion without traditional repiping methods.

What Is Pipe Corrosion?

Pipe corrosion is the gradual breakdown of a pipe’s structure caused by chemical, electrochemical, or environmental reactions. It can occur on the inside or outside of pipes when the pipe material is exposed to corrosive elements.

Although corrosion is most often associated with metal pipes, non-metal piping systems can also experience material degradation, damage, or failure depending on water chemistry, installation conditions, temperature, pressure, and chemical exposure.

Common types of corrosion and pipe deterioration include:

• Galvanic corrosion
• Pitting corrosion
• Crevice corrosion
• Uniform corrosion
• Hydraulic wear
• Chemical-related pipe degradation

What Types of Pipes Can Corrode or Fail?

Water pipes are commonly made from steel, copper, PVC, CPVC, or PEX. Each material has different strengths, limitations, and potential failure risks.

Galvanized Steel Pipes

Galvanized steel pipes are steel pipes coated with zinc. They were commonly used in older homes and buildings, but they are less common today because they are labor-intensive to cut, thread, and install.

These pipes are still found in some older residential and commercial plumbing systems. In many cases, galvanized steel pipes have a functional life of about 40 to 50 years, but corrosion and buildup can reduce performance over time.

Copper Pipes

Copper pipes are widely used for hot and cold water distribution. They can be installed above ground or underground, though underground copper piping may require a protective sleeve depending on soil conditions.

Copper piping is often expected to last more than 25 years. However, changes in drinking water treatment, including the use of chloramines, may contribute to pinhole leaks in some systems in less than five years.

PVC and CPVC Pipes

PVC is a plastic piping material commonly used in plumbing and was one of the first plastic alternatives to copper. PVC is typically used for cold water applications because heat can affect the material.

CPVC is designed for hot water lines and can be used where PVC is not appropriate. PVC and CPVC pipes are often expected to last 50 to 75 years, but failures can still occur depending on installation quality, water conditions, temperature, pressure, and chemical exposure.

PEX Pipes

PEX is flexible plastic piping that can be used for hot and cold water lines. It is also common in radiant under-floor heating systems.

PEX piping is often expected to last more than 25 years, but changes in water treatment, including chloramines, may contribute to early failures or pinhole leaks in certain systems.

What Causes Pipe Corrosion?

All piping systems are affected by time, water chemistry, and environmental conditions. While some corrosion is expected as pipes age, several factors can speed up the process.

Common causes of pipe corrosion include:

Electrochemical activity
Improper grounding of electrical appliances to copper pipes, nearby electrical wiring, or lightning-related electrical activity can contribute to corrosion.

Sand, dirt, and sediment buildup
Sediment and contamination in the water can create hydraulic wear, buildup, and corrosion inside the pipe.

Plumbing installation issues
Improper installation, incompatible materials, and excessive use of chemical drain cleaners can damage pipes and increase corrosion risk.

High water velocity
When water moves too quickly through pipes, especially in systems with pumps or circulating hot water lines, it can cause hydraulic wear and accelerate internal pipe damage.

High water temperature
Excessively hot water can place stress on piping materials and increase the likelihood of corrosion or premature failure.

What Are the Effects of Pipe Corrosion?

Pipe corrosion can create both visible and hidden problems. In some cases, the first sign may be a small leak. In more severe cases, corrosion may already be affecting the entire plumbing system.

Common effects of pipe corrosion include:

• Lead or copper entering drinking water
• Pipe leaks and pinhole leaks
• Stained sinks, tubs, and fixtures
• Odors or unpleasant water quality issues
• Reduced water flow
• Plumbing system failure
• Costly repairs or full repiping
• Water damage that may not be fully covered by insurance

If copper pipes corrode, copper may leach into drinking water. In older homes built before 1986, lead exposure may also be a concern if the plumbing system has not been replaced or properly treated.

When corrosion becomes severe, the damage may affect more than one pipe section. Internal corrosion can reduce flow, weaken pipe walls, create pits or pinholes, and eventually cause major leaks or complete pipe failure.

How Much Can Pipe Corrosion Cost?

The cost of pipe corrosion can vary widely. A small corroded section may require a minor repair, while widespread internal corrosion can lead to thousands or even tens of thousands of dollars in repair and restoration costs.

Water damage can also become expensive quickly. While some homeowner’s insurance policies may cover sudden water damage, many policies exclude damage that happens gradually over time, such as slow leaks or long-term pinhole leaks.

That is why early inspection, corrosion control, and pipe restoration are important.

How Can You Help Prevent Pipe Corrosion?

You may not be able to completely prevent pipe corrosion, but you can take steps to slow it down and reduce the risk of severe damage.

Use corrosion inhibitors

Corrosion inhibitors are chemical substances added to water to help slow the rate of corrosion inside piping systems.

Keep pipes away from electrical wiring

Reducing contact between pipes and electrical wiring may help minimize electrochemical corrosion risk.

Install calcite neutralizer filters when appropriate

Calcite neutralizer filters can help reduce water corrosivity by raising pH. However, they may also increase water hardness, so a water softener may be needed in some properties.

Control water velocity

If water moves too quickly through pipes, it can accelerate internal wear. Proper pipe sizing helps maintain good flow while reducing excessive velocity.

Manage hot water temperature

Very high water heater settings can increase the risk of burns and may also contribute to pipe problems. Keeping water temperature within a safe and appropriate range can help protect both people and plumbing systems.

How Do You Treat Pipe Corrosion Correctly?

Ignoring corrosion usually allows the problem to get worse. If you notice leaks, discolored water, reduced flow, stains, odors, or recurring plumbing issues, it is important to have the system inspected.

ePIPE provides pipe restoration solutions that can help address corrosion without traditional repiping in many cases. Instead of tearing out and replacing large sections of pipe, ePIPE’s epoxy coating process is designed to restore the inside of the existing pipe structure.

This approach can help property owners save time, reduce disruption, and avoid many of the costs associated with conventional repiping.

Why Choose ePIPE for Pipe Corrosion Repair?

ePIPE helps homeowners, building owners, and property managers evaluate corrosion issues and determine the best course of action for corrosion control and pipe restoration.

Benefits of ePIPE may include:

• In-place pipe restoration
• Reduced need for demolition
• Less disruption than traditional repiping
• Leak and corrosion control support
• Solutions for residential, commercial, and specialty projects
• 24/7 emergency support
• Financing options