Top 10 Most Common Plumbing Issues in Homes

As a professional home inspector, I'd like to share insights into some of the most common plumbing challenges that I encounter in homes, which, if neglected, can lead to significant problems.

One of the most significant health risks associated with plumbing leaks is mold and mildew growth. These fungi thrive in moist environments, and even a small, persistent leak can create the perfect conditions for them to flourish. Exposure to mold can cause a variety of health issues, particularly for individuals with allergies, asthma or compromised immune systems. Symptoms can include respiratory distress, coughing, sneezing, and in severe cases, chronic lung illnesses.

Moreover, leaks can also indirectly contribute to the deterioration of indoor air quality. As materials like wood, drywall, and insulation absorb water, they can begin to break down, releasing volatile organic compounds (VOCs) and other harmful substances into the air. These contaminants can cause headaches, eye irritation, fatigue, and other health problems, especially when inhaled over an extended period.

Meanwhile, standing water from leaks can become a breeding ground for bacteria and insects, which can lead to waterborne diseases and pest-related health issues. Stagnant water is known to attract mosquitoes, which can carry diseases like the West Nile Virus and Zika, while bacteria such as Legionella, which causes Legionnaires' disease, can proliferate in leaking, standing water associated with HVAC systems.

Leaks that reach electrical systems pose an immediate risk of injury from electric shock, but they can also cause chronic problems due to the degradation of electrical wiring insulation, leading to potential fires and associated smoke inhalation risks.

Furthermore, if a leak reaches the foundation of a home, it can lead to structural damage. Inhabitants may be exposed to unsafe living conditions, including the risk of collapse or falling debris. Such an environment is not only physically hazardous but can also contribute to psychological stress and anxiety, impacting mental health.

10 Most Common Plumbing Issues in Homes

Besides the naturally occurring rot and mold resulting from water damage, plumbing leakage can expose you and your family to harmful contaminants like E. coli bacteria or salmonella. Here are some of the most plumbing issues I encounter in homes while I’m out in the field:

1. Leaking Pipes: These leaks, often found under sinks, can escalate from minor drips to serious problems like water damage, rot, and mold if not addressed promptly. They are the most common plumbing issues that home inspectors see in both supply and drain pipes. Most Americans, due to the poor visibility of pipes, do not check their drainage and supply pipes for leaks and therefore don’t typically notice serious issues until water damage builds and/or mold growth arises. Even small leaks denoted by a slow trickle can turn into severe water damage, rot and mold. I regularly check under sinks during my inspections to ensure pipe leaks aren’t posing a threat to your greatest investment and the health and safety of your family in the long run.

2. Improperly Pitched Drains: For effective drainage, pipes need a proper pitch towards the sewer. The standard is a ¼” per foot slope, though 1/3” per foot is acceptable for pipes 3” in diameter or larger. When this pitch is incorrect, it can lead to leaks and slow drainage.

3. Corrugated Drain Pipes: While they're readily available in hardware stores, corrugated drain pipes are not recommended due to their tendency to clog and difficulty in cleaning. I often find corrugated drain pipes under kitchen or bathroom sinks due to improper installation by a homeowner or unlicensed plumber. Plumbing standards forbid these types of drain pipes due to their tendency to clog and cleaning difficulty. Smooth interior walled pipes are the standard in plumbing.

4. Water Heater Safety Concerns: A crucial component of modern water heaters is the temperature and pressure (T&P) relief valve with a proper discharge pipe. This setup is vital to prevent potential explosions or damage from overheating or excessive pressure. A T&P valve opens with adequate pressure buildup or temperature increase. Without it, the water heater has the potential to explode or shoot up through the home’s infrastructure due to the immense power generated by pressure and heat buildup. The discharge pipe should be hot water-rated, visible near the water heater, non-threaded at the end, and match the valve's diameter (typically ¾”). Hot water-rated materials exclude PVC and ABS material, unless printed otherwise on the pipe. The discharge pipe should also be readily visible to the homeowner and should terminate around 6” above the adjacent floor.

5. Overheated Water Heaters: Hot water in homes should not exceed 120 degrees Fahrenheit to prevent scalding risks. Water exceeding this temperature does not only pose a safety hazard, but also leads to unnecessary energy consumption. For boilers doubling as water heaters, a mixing valve can regulate the temperature to safe levels. Mixing valves add a splash of cold water to the hot water supply line to prevent dangerous heat spikes. Even just a 4-6-second splash of 140 degree Fahrenheit water can lead to 2nd or 3rd degree burns, and young children and the elderly are even more susceptible to serious, internal damage from hot water.

6. Missing Traps in Plumbing Fixtures: Traps in drain pipes are essential in plumbing fixtures to block sewer gases and pests from entering the home. Toilets, for instance, have traps used to prevent sewer gases and vermin from entering the home through drain pipes – and these fixtures are typically overlooked and uninstalled by unqualified plumbers and homeowners. A lack of trap is evidenced by a strong sewage smell during points of entry, including laundry and dishwasher drains. To prevent clogs, drain lines should limit their traps to 1.

7. Slow Drains: Commonly caused by hair clogs or foreign objects, slow drains are a frequent issue in many homes. While sometimes simple to fix with a plunger, they can also indicate more serious problems like damaged or blocked main sewer lines, particularly in older homes. Older drain pipes might have tree roots growing into them. A licensed home inspector can identify drain issues using a small camera snaked along the line. WIN Home Inspection offers a Sewer Scope Inspection for this purpose, ensuring your sewage system is devoid of blockages and potential leaks and intrusions. Contact your local WIN home inspector today for further information. In the event your drain needs unclogging, we don’t recommend using drain clearing chemicals due to their potential to backsplash and burn.

8. Loose or Leaking Toilets: Toilets can loosen over time, which can break the seal with the floor, leading to water leaks and potential subfloor damage. A moisture meter is a handy tool to detect unseen moisture around the toilet's base, which could indicate a need for repair or reseating with a new wax ring. To check the security of your toilet, we recommend gently rocking the device. Discolored flooring is also an indication of moisture buildup from leakage. Typically, repairs for issues of this nature involve reseating the toilet with a fresh wax ring – however, issues can extend beyond the toilet seat. An evaluation by a licensed professional is the best way you can identify and mitigate toilet-related issues, so they don’t interfere with the health and safety of you and your family.

9. Dishwasher Drainage Issues: Dishwasher installation instructions often call for a high loop or an air gap in the drain line. This setup prevents contaminated water from re-entering the dishwasher, an important detail I frequently find overlooked in homes. Upon discharge, high loops and air gaps prevent dirty, contaminated water from the sink drain from re-entering the your dishwasher water system.

10. Non-Functional Drain Stoppers: In both old and new homes, I regularly find bathtubs with malfunctioning drain stoppers. Older tubs might have issues with their chain systems, while newer ones may have worn-out toe-tapper stoppers. Replacing these parts is generally an easy fix that can greatly improve the functionality of the tub. Sometimes, however, tub stopper chains degrade and detach over time until they become stuck in place. A licensed plumber can mitigate this issue.

The Importance of Vigilance and Maintenance in Plumbing Systems

Here are some reasons why proper vigilance and maintenance of plumbing systems are important:

• Prevention of Leaks and Water Damage: Regular checks can identify weak spots or corrosion in pipes before they lead to leaks. Leaks can cause significant damage to a home’s structure, leading to costly repairs and potential mold growth.

• Avoidance of Health Risks: Standing water or leaks can lead to mold and mildew, which are health hazards, particularly for those with allergies or respiratory issues. Well-maintained plumbing also prevents backflow incidents that could contaminate drinking water.

• Preservation of Water Quality: Properly maintained plumbing systems ensure the water supply remains free from contaminants. This is crucial for maintaining the health of the home’s inhabitants.

• Efficient Functioning: Regular maintenance ensures that plumbing fixtures and pipes work efficiently. This means less likelihood of blocked drains or reduced water pressure, which can be inconvenient and expensive to rectify.

• Energy and Cost Savings: A well-maintained plumbing system is more efficient, which can lead to reduced water bills and energy costs. For instance, a dripping faucet or a leaking pipe can waste a significant amount of water over time.

• Longevity of Plumbing Systems: Regular maintenance can extend the life of your plumbing system by addressing small issues before they become big problems that require extensive and expensive replacements.

• Environmental Protection: By preventing leaks and reducing the chance of toxic materials entering the ecosystem, good plumbing maintenance contributes to environmental conservation.

• Compliance with Warranty and Insurance Policies: Many warranty and home insurance policies require a certain level of maintenance. Keeping up with plumbing maintenance helps ensure that you comply with these policies, which can be crucial in the event of a claim.

• Peace of Mind: Knowing that your plumbing system is in good working order provides peace of mind, as the risk of sudden failures and the inconveniences they bring is greatly diminished.

Remember, regular plumbing checks and maintenance can prevent these common issues from becoming major headaches. I recommend that you are proactive in maintaining your plumbing systems to ensure a safe and comfortable living environment. Careful monitoring also ensures your plumbing system is operationally sound.