When buying a house in Denver, CO, you should pay close attention to the plumbing system. Freeze-thaw cycles, mineral-rich water, and shifting soil can all affect buried pipes and plumbing fixtures over time. Small leaks, aging pipes, or drainage issues often remain hidden behind finished walls or under concrete floors. Tree roots sometimes invade older pipes through tiny gaps and holes in search of moisture underground.
While a general home inspection is usually required, it may not catch all the problems in the plumbing system. A professional plumbing inspection helps uncover hidden problems before you finalize the purchase. Our team at Summit Heating, A/C, Plumbing & Electrical regularly inspects homes across Denver and often finds plumbing issues that buyers and general inspections missed.
Water Service Line
The water service line brings fresh water from the city main into the house. Many older Denver homes still have galvanized steel service lines. Over time, these pipes corrode internally. Rust buildup slowly narrows the pipe diameter, which reduces water pressure throughout the home. Low pressure at multiple fixtures may indicate corrosion or even a small underground leak. Wet soil near the foundation can also suggest a damaged service line.
During a professional inspection, our plumbers measure water pressure and examine any visible piping materials. Since property listings rarely mention the service line’s age, an inspection can reveal important information before closing.
Main Shutoff Valve
Every home should have a working main water shutoff valve inside the building. It stops the entire water supply during emergencies. Most homes place the shutoff valve near the water meter or where the service line enters the basement. If unused for years, mineral deposits may cause it to seize.
Testing the valve helps confirm it still operates properly. Some Denver homes still have older gate valves rather than modern ball valves. Gate valves contain internal parts that wear down over time and may no longer seal fully. If it cannot close completely, a leak or burst pipe becomes much harder to control. Replacing an aging valve is usually a simple upgrade, but you’ll want this information before closing.
Water Heater
Most homes use either traditional tank heaters or high-efficiency tankless units. You can check the manufacturer’s label to determine the heater’s age. Tank water heaters typically last 8–12 years, and tankless systems often last up to 20 years.
However, these lifespans are dependent on having regular maintenance. Denver’s mineral-heavy water often leads to sediment buildup inside the tank. Over time, that sediment reduces heating efficiency and can damage the tank’s internal lining. Rust around the base of the heater may indicate internal corrosion. A leaking tank usually requires replacement. Gas water heaters should also have proper venting to safely carry combustion gases outside. We can investigate these issues and estimate the remaining service life.
Supply Lines
Supply lines carry water from the main line to fixtures throughout the home. Pipe materials vary depending on the home’s age. Common materials include copper, PEX, CPVC, and older galvanized steel.
Galvanized pipes frequently appear in homes built before the 1960s. As these pipes age, internal corrosion gradually restricts water flow. Uneven pressure between fixtures can sometimes indicate partially blocked supply lines. Discolored water may also appear when corrosion flakes break loose inside older pipes.
Any visible pipe connections should remain dry. Mineral crust, rust staining, or green marks around copper fittings often suggest slow leaks.
Drain Pipes
Drain pipes remove wastewater from sinks, tubs, showers, and appliances. Many older Denver homes still have cast-iron drain pipes. Cast iron is durable, but it eventually corrodes from the inside out. As rust flakes develop, they can restrict water flow and trap debris.
During renovations, homeowners often replace them with corrosion-resistant PVC. However, poor installation can create low spots in the pipe, known as belly sections. These areas collect debris, causing slow drains.
Sewer Line
All wastewater flows through the sewer line to the municipal system. This pipe runs underground from the foundation to the city connection. Because sewer lines run underground, damage often goes unnoticed.
Tree roots are a common issue in Denver. Roots naturally seek moisture and can slip into small cracks in clay or cast-iron pipes. Once inside, they trap debris and gradually block the line. Signs of sewer line trouble may include multiple slow drains or gurgling sounds in plumbing fixtures. A sewer camera inspection is the most reliable way to assess the condition of underground pipes.
Sump Pump
Many Denver basements rely on sump pumps to remove groundwater from around the foundation and basement. The pump sits in a sump basin installed below the basement floor. Snowmelt and spring storms can increase groundwater pressure around the home. If the sump pump fails, water may begin collecting on the basement floor.
Inspect the discharge pipe to make sure it directs water away from the foundation. The system should also include a check valve to prevent discharged water from flowing back into the basin.
Faucets and Fixtures
Faucets and fixtures can reveal useful clues about the overall plumbing system. Running several fixtures at once helps you evaluate both pressure and drainage. Strong, steady flow usually indicates healthy supply lines. Weak pressure or sputtering water may point to pipe corrosion or hidden leaks.
Dripping faucets often mean worn cartridges or mineral buildup inside the fixture. While these repairs are usually minor, they can signal larger maintenance issues in older homes. It’s also worth checking under sinks for moisture, corrosion, or water stains. Even slow leaks inside cabinets can eventually damage wood and encourage mold growth.
Toilets
Toilets connect both the supply and drainage sides of the plumbing system, making them useful indicators of overall performance. During a walkthrough, flush each toilet and observe how quickly the tank refills. A weak flush may suggest clogged rim jets or a partially blocked drain line. A worn flapper valve may cause the toilet to keep running after the tank refills.
Also, check the floor around the base of the toilet. Soft flooring, staining, or discoloration can indicate a leaking wax seal beneath the fixture.
Laundry Connections
Laundry rooms contain several plumbing connections operating at the same time. Washing machines require both hot- and cold-water supply lines along with a standpipe drain. The appliances create constant vibration during cycles. A burst hose can release large amounts of water in a short time. Older rubber hoses can crack or weaken after years of pressure and movement. Stainless steel braided hoses are far more durable and resist bursting.
The standpipe drain should extend above the washing machine’s water level. This height prevents wastewater from siphoning back into the appliance.
Outdoor Plumbing
Outdoor plumbing components also deserve attention when evaluating a property. Denver winters bring freezing temperatures that can damage exposed pipes. Exterior hose bibs should use frost-proof designs that keep the valve seat inside the heated portion of the wall. Older faucets sometimes crack if water remains trapped inside during freezing weather. Look closely at the siding around hose connections. Water stains or damaged materials may indicate past leaks.
Homes with irrigation systems should also have a backflow prevention device installed. This device prevents contaminated sprinkler water from entering the home’s drinking supply.
Get a Thorough Plumbing Inspection from Summit Heating, A/C, Plumbing & Electrical
Our team at Summit Heating, A/C, Plumbing & Electrical provides comprehensive plumbing system inspections. We also provide sewer camera inspections, water heater service, leak detection, and pipe repairs for homeowners across Denver. If you’re buying a home, our professional plumbing inspection can help identify hidden issues before closing. Contact Summit Heating, A/C, Plumbing & Electrical today to schedule a pre-purchase plumbing inspection.
