🧰 What’s Inspected During a Plumbing System Inspection — and Why It Matters

When it comes to protecting your investment, the plumbing system is one of the most critical areas of a home inspection. A properly functioning plumbing system ensures safe drinking water, effective waste removal, and overall home comfort. At Mook Home Inspections LLC, we follow InterNACHI’s Standards of Practice to thoroughly evaluate the condition and performance of a home’s plumbing components — helping our clients make informed decisions before they buy or sell.

🔍 What’s Included in a Plumbing System Inspection

According to InterNACHI’s Standards of Practice, a plumbing system inspection includes a non-invasive, visual examination of accessible plumbing components. During your home inspection, we’ll assess:

1. Main Water Supply and Distribution

• Identification of the main water shutoff valve

• Type and condition of supply piping materials (copper, PEX, galvanized steel, etc.)

• Water pressure and visible signs of leaks or corrosion

2. Drain, Waste, and Vent (DWV) System

• Type and condition of drain materials (PVC, cast iron, etc.)

• Proper drainage and venting to prevent sewer gas backup

• Functional flow testing at multiple fixtures to confirm proper drainage

3. Fixtures and Faucets

• Toilets, sinks, bathtubs, and showers checked for operation and leaks

• Inspection of faucet handles, diverters, and drains for proper function

• Signs of water damage, staining, or moisture beneath cabinets and around fixtures

4. Water Heater

• Identification of type (gas, electric, tankless) and age

• Proper T&P (temperature and pressure) relief valve installation and discharge piping

• Visible corrosion, leaks, or inadequate venting

5. Fuel and Venting Systems

• Inspection of visible gas lines for corrosion or improper materials

• Verification of safe combustion venting for gas-fired water heaters

⚠️ Common Plumbing Defects Found During Home Inspections

Even newer homes can have plumbing issues that go unnoticed. Some of the most common defects we discover include:

• Leaking or corroded pipes — often due to aging materials or improper installation

• Improper drain slope — leading to slow drainage and frequent clogs

• Cross-connections — where potable water and waste lines are improperly joined

• Leaking fixtures or running toilets — causing water waste and higher utility bills

• Unsecured or unsupported piping — which can cause strain and noise in the system

• Water heater problems — including missing expansion tanks, rusted tanks, or unsafe venting

• Improperly installed P-traps — allowing sewer gases to enter the living space

💧 Why a Plumbing System Inspection Is So Important

A plumbing inspection is about more than just finding leaks — it’s about protecting your health, safety, and finances.

1. Prevent Costly Repairs: Undetected leaks can lead to water damage, mold growth, and thousands of dollars in structural repairs.

2. Ensure Safe Water Quality: Faulty pipes or cross-connections can compromise your drinking water.

3. Maintain Efficiency: Catching minor issues early can improve water pressure, reduce waste, and extend the lifespan of fixtures and water heaters.

4. Peace of Mind: Whether you’re buying, selling, or maintaining your home, a plumbing inspection gives you confidence that the system is functioning safely and efficiently.

🏡 Trust Mook Home Inspections LLC

At Mook Home Inspections LLC, we take pride in providing thorough, unbiased evaluations of every system in your home — including the plumbing. Our inspections follow InterNACHI’s Standards of Practice to ensure nothing is overlooked and every client receives a detailed, easy-to-understand report.

If you’re preparing to buy, sell, or maintain your property, schedule your next inspection with confidence.

📞 Call Mook Home Inspections LLC today for a comprehensive home inspection and peace of mind tomorrow.