How to Check Plumbing When Buying a House (Avoid Costly Mistakes!)

Buying a home is one of the biggest financial decisions you’ll ever make—and hidden plumbing issues can turn your dream home into a money pit. How to check plumbing when buying a house isn’t just about running the taps; it’s about uncovering potential leaks, outdated materials, and future repair costs before you sign on the dotted line. In this guide, you’ll learn exactly what to look for, step by step, through practical tips trusted by real estate pros and licensed plumbers alike.

Why Plumbing Matters More Than You Think

According to the American Society of Home Inspectors (ASHI), plumbing problems rank among the top 5 most common issues found during home inspections. From corroded pipes to inefficient water heaters, plumbing failures can cost homeowners $500 to $10,000+ in repairs—sometimes within weeks of moving in.

And it’s not just about cost. Poor plumbing can lead to mold growth, structural damage, and even health hazards. That’s why a thorough plumbing check isn’t optional—it’s essential.

1. Should You Hire a Professional Inspector? (Yes—But Know What They’ll Do)

While it’s tempting to rely solely on your general home inspector, not all inspectors specialize in plumbing. A licensed plumber or a certified home inspector with plumbing expertise can spot red flags you might miss.

A professional will typically:

• Inspect visible pipes for corrosion, leaks, or improper materials (e.g., galvanized steel or polybutylene)
• Test water pressure (ideal: 40–80 psi)
• Check the age and condition of the water heater
• Run multiple fixtures simultaneously to assess flow and drainage

💡 Pro Tip: The U.S. Department of Housing and Urban Development (HUD) recommends hiring a separate plumbing inspector if the house is over 25 years old or shows signs of water damage.

For context, polybutylene pipes—common in homes built between 1978 and 1995—were linked to widespread failures and are now banned. Learn more about polybutylene plumbing on Wikipedia .

2. How to Visually Inspect Plumbing Yourself (Even as a Beginner)

You don’t need a plumbing license to spot warning signs. Here’s a simple DIY plumbing checklist to use during your walkthrough:

✅ Check Under Sinks

• Look for water stains, mold, or warped cabinets
• Feel pipes for moisture or corrosion
• Open and close shut-off valves—do they work smoothly?

✅ Test All Fixtures

• Turn on every faucet, shower, and tub—hot and cold
• Flush all toilets—listen for continuous running or weak flushes
• Run the dishwasher and washing machine (if possible)

✅ Look for Low Water Pressure

• Weak flow in multiple fixtures may signal pipe corrosion or blockages
• Compare pressure between upstairs and downstairs—big differences suggest pipe issues

✅ Inspect the Water Heater

• Note the manufacture date (typically on a sticker)—most last 8–12 years
• Check for rust, leaks, or sediment buildup at the base

3. What Are the Most Dangerous Plumbing Red Flags?

Not all plumbing issues are created equal. These are the deal-breakers that warrant negotiation—or walking away:

📊 Stat Alert: The EPA estimates that the average household loses 10,000 gallons of water annually due to leaks—enough to wash 270 loads of laundry!

4. Step-by-Step: How to Conduct a Basic Drain Test

A slow drain might seem minor—but it could signal a major blockage or pipe collapse. Here’s how to test drainage properly:

1. Fill two sinks (e.g., kitchen and bathroom) with about 2 liters of water each.
2. Simultaneously pull both plugs.
3. Time how long it takes for the water to fully drain.
   • Healthy drains: < 15 seconds
   • Slow drains: > 30 seconds → possible clog or venting issue
4. Listen for gurgling sounds—this suggests improper venting or partial blockage.

Repeat this test after running the shower or flushing toilets to simulate real-world water demand.

5. Ask the Right Questions Before Closing

Don’t assume sellers will volunteer plumbing history. Ask directly:

• “Has the home ever had a sewer backup or insurance claim for water damage?”
• “When was the last time the water heater was serviced?”
• “Are there any known pipe materials like galvanized steel or polybutylene?”
• “Can you provide permits for past plumbing work?”

In many states, sellers are legally required to disclose known defects—but they won’t mention issues they’re unaware of.

FAQ Section

Q: Can I skip a plumbing inspection if the house looks clean?

A: Absolutely not. Many serious plumbing issues (like hidden leaks or corroded pipes inside walls) show no visible signs. A professional inspection is your best defense against six-figure surprises.

Q: How much does a plumbing inspection cost?

A: Typically $150–$500, depending on location and home size. It’s a small price compared to potential repair bills.

Q: What if the inspector finds a problem?

A: You can negotiate repairs, request a price reduction, or ask for a home warranty that covers plumbing. In severe cases (e.g., lead pipes), you may choose to walk away.

Q: Are older homes more likely to have plumbing issues?

A: Yes. Homes built before 1980 often use outdated materials like cast iron, galvanized steel, or lead pipes—all prone to failure. Always get a full plumbing assessment for vintage properties.

Q: Can I test water quality during a home tour?

A: You can request a water test as part of your inspection contingency. This is especially important for homes with well water or in areas with known contamination risks.

Q: Does homeowner’s insurance cover plumbing repairs?

A: Usually only if the damage is sudden and accidental (e.g., a burst pipe). Gradual leaks, corrosion, or maintenance issues are typically excluded.

Conclusion

Knowing how to check plumbing when buying a house empowers you to avoid costly, stressful surprises—and protects your biggest investment. From testing faucets to decoding pipe materials, a little diligence goes a long way.

👉 Don’t gamble on plumbing. Hire a qualified inspector, use this checklist, and ask tough questions. Your future self (and your wallet) will thank you.

Found this guide helpful? Share it with a friend who’s house hunting! 🏡💧
#HomeBuyingTips #PlumbingChecklist #SmartHomebuying