If you're living in an older Seattle home, chances are your plumbing system has aged right along with it. While you may not think about your pipes until something goes wrong, the reality is that plumbing failures often happen behind the scenes—until they cause major (and costly) damage.
We help Seattle homeowners like you identify the warning signs of aging plumbing early, so you can take proactive steps before a leak or backup causes damage to your home.
1. Common Plumbing Problems & Signs They Might Be Failing
2. When Should You Replace Plumbing?
3. Why We Recommend PEX in Modern Homes
4. What Seattle Homeowners Should Do Next
Plumbing systems don’t last forever, and certain materials used in older homes—like galvanized steel, copper, cast iron, clay, or concrete—are particularly prone to corrosion and failure over time.
Here’s what to look for:
If your Seattle home was built before the 1960s, it may still rely on galvanized steel pipes—a material that was once standard but is now known for its tendency to corrode from the inside out. Over time, rust and mineral buildup accumulate within the pipe walls, shrinking the interior diameter and causing a wide range of plumbing issues that worsen with age.
What it means: Galvanized pipes commonly suffer from internal corrosion and buildup, which restricts water flow. As the interior narrows, you may notice low water pressure or weak flow from faucets and showerheads—especially when multiple fixtures are in use.
Why it matters: Reduced flow isn’t just inconvenient; it’s often a red flag that your plumbing system is deteriorating and may be approaching failure.
What it means: As galvanized pipes age, they begin to corrode from the inside, causing tiny flakes of rust and metal to break off and travel through your plumbing system. These particles often end up in aerators (the small mesh screens at the tips of faucets) and mixing valves (which regulate your hot and cold water). If you find yourself frequently unscrewing and cleaning faucet screens, this is a clear sign that your pipes are deteriorating.
Why it matters: This buildup can lead to reduced water flow, temperature imbalances (such as only receiving cold water or hot water in the shower), and constant, frustrating maintenance. It could be an early warning that your plumbing system may be nearing the end of its useful life and should be evaluated by a professional plumber.
What it means: Galvanized water lines are especially vulnerable at joints, elbows, and connection points—areas where water changes direction or pressure increases. These spots tend to corrode more quickly, resulting in small leaks that can remain undetected for weeks or even months.
Why it matters: Leaks at joints are especially problematic because they often occur behind walls or under floors. Even a slow drip can result in mold growth, wood rot, or water damage to drywall and insulation before you notice visible signs. By the time it’s discovered, you may be facing more than a plumbing repair—you could be looking at major home restoration work.
Toilets are one of the most-used fixtures in the home, and one of the first to show signs of a plumbing problem. Here are some common issues to watch for:
Running toilets: Often caused by a worn-out flapper or a faulty fill valve, a running toilet can waste hundreds of gallons of water per day and increase your water bill.
Slow-filling tanks: This could be due to sediment buildup in the fill valve or issues with your water supply pressure.
Frequent clogged toilets or slow flushes: These issues may be caused by a localized blockage, a problem in your main sewer line, or even tree roots interfering with the flow.
Phantom flushes: If your toilet occasionally refills without being used, it’s likely a sign of a small leak between the tank and bowl.
What to do: Start by inspecting the internal components of the toilet tank. Replacing a flapper or fill valve is often a simple DIY repair. If issues persist, or you notice clogs in multiple toilets or drains, it’s time to call a professional for a full inspection.
Copper piping is known for its durability, but the longevity of this material depends heavily on the pH level of your water. If the water in your home is too acidic (low pH) or too alkaline (high pH), it can accelerate corrosion inside the pipes. Over time, this internal breakdown can cause the copper to dissolve into your water supply, weakening the pipe walls and potentially affecting water quality.
Why it matters: Corroded copper pipes can lead to leaks, water discoloration, and even a metallic taste in your drinking water. In more advanced cases, tiny pinhole leaks can form—especially in areas that are not visible, such as behind walls or under floors—causing slow, hidden water damage over time. Additionally, water chemistry that’s out of balance also shortens the lifespan of your water heater and other important plumbing fixtures.
What to do:
Test your water’s pH regularly—ideally, it should be between 6.5 and 8.5. You can use a home test kit, a digital pH meter, or consult a professional for more accurate results.
Watch for warning signs:
Discoloration in your tap water
A metallic taste when drinking water
Small leaks or unexplained water stains
Plan ahead if your home has aging copper pipes: If you’re opening walls during a remodel, it’s the perfect time to evaluate and potentially replace old piping. Upgrading during construction is far easier—and cheaper—than dealing with a leak after the fact.
If you live in an older Seattle home, there’s a good chance your sewer line is made of cast iron, clay, or concrete—materials that were commonly used before modern alternatives like PVC or HDPE became standard. While these materials were durable for their time, they’re prone to specific issues as they age—and can cause serious problems beneath the surface.
Common issues and what they mean:
Corrosion in cast iron: Over time, cast iron pipes rust from the inside out. This leads to thinning walls, cracks, or full pipe collapses, especially at joints and connection points. Corroded interiors can also trap debris, contributing to slow drainage and clogged drains.
Tree roots infiltrating clay or concrete joints: Clay and concrete sewer pipes were often installed in short sections that fit together without the use of adhesives. This makes them vulnerable to root intrusion. As trees grow, their roots seek out moisture and can easily invade small gaps between pipe sections, eventually causing burst pipes or total blockages.
Blockages from debris or buildup: Older concrete or cast iron sewer lines often have rough or uneven interiors caused by mineral deposits and corrosion, which can snag toilet paper, wipes, or other materials that shouldn’t go down the drain. Over time, this leads to clogs and backups, and often with little warning.
Sewage backups into lower levels of your home: When a sewer line is blocked or collapses, wastewater has nowhere to go. The result is a plumbing emergency. It comes back up through your drains, often in the lowest part of the home—like a basement floor drain or basement bathroom. The damage (and the cleanup) can be extensive, expensive, and, frankly, disgusting.
Why it matters: Unlike water supply lines, sewer lines are out of sight and often out of mind—until something goes terribly wrong. Because these pipes are buried underground, problems often go unnoticed until symptoms appear inside your home, such as slow drains, foul odors, gurgling toilets, or raw sewage backing up. At that point, plumbing repairs can be invasive and costly.
What to do:
Schedule a plumbing inspection via camera. If you suspect sewer line issues, it’s a quick, non-invasive way to check for cracks, root intrusion, or buildup.
Install a backwater valve to prevent wastewater from flowing back into your home in the event of a blockage or city sewer backup.
Add a cleanout access point near your home’s exterior to make regular maintenance easier and less disruptive.
Install a sump pump in the basement or crawlspace to help protect against flooding, backups, or water accumulation caused by heavy rains or sewer issues.
If your sewer line is nearing or past its expected lifespan, consider proactively replacing it, whether partially or fully—especially during major landscaping or driveway work when access is easier.
We get this question a lot. The honest answer? Plumbing can last for decades or fail next week. There’s no one-size-fits-all rule, but here are some general guidelines:
If your plumbing is exposed during a remodel, it’s the ideal time to replace it. This minimizes costs and disruption, and avoids the risk of damaging your brand-new finishes later.
When relocating plumbing fixtures (such as a kitchen sink), Seattle code often requires bringing the plumbing up to modern standards.
If your water tests show concerning pH levels, corrosion may already be happening inside your pipes—even if you can't see it, and may warrant an upgrade.
Pro Tip: If you’re opening up walls, taking them down, or touching the ceiling during a remodel, this is the ideal opportunity to do so. It’s always more cost-effective (and less stressful) to update aging plumbing now than to deal with major problems down the road.
New construction and remodels today almost always use PEX (cross-linked polyethylene) piping—and for good reason.
Flexible and lightweight: PEX can bend around corners and obstacles without needing multiple fittings or joints, which means fewer potential points where water leaks and lower labor costs. It also speeds up installation, saving time and money on remodels.
Resistant to corrosion and mineral buildup: Unlike galvanized steel or copper, PEX won’t corrode or degrade due to water chemistry. It’s safe for use with acidic, alkaline, or hard water and helps ensure a long-lasting, low-maintenance plumbing system.
Better freeze resistance: PEX expands slightly under pressure, making it less likely to crack if exposed to freezing temperatures—a major advantage in uninsulated areas or during Seattle cold snaps.
Quieter water flow: Because it’s flexible, water moves through PEX more smoothly than metal piping, which means less vibration and rattle in the walls—especially when multiple fixtures are running.
Color-coded hot and cold lines: Red for hot, blue for cold—it sounds simple, but it makes troubleshooting and future repairs easier and faster for any plumber or homeowner down the line.
Things to know:
Not suitable for outdoor or exposed installations: PEX breaks down quickly when exposed to UV rays, making it unsuitable for use outdoors or in areas that receive direct sunlight.
Not recyclable: Unlike copper or some other plastics, PEX can’t currently be recycled, which may be a consideration for eco-conscious homeowners.
DIY installation is challenging and not recommended: PEX requires specialized crimping or expansion tools to make leak-free connections—tools most homeowners don’t own. For reliability and code compliance, it’s always best to hire a professional plumber to handle installation.
Aging plumbing doesn’t have to be a ticking time bomb. With some foresight and a few smart choices, you can keep your home safe, functional, and protected for the long haul.
Download our free Home Plumbing Inspection Checklist to spot early warning signs, plan smart upgrades, and protect your Seattle home from costly damage.
At Better Builders, we specialize in creating functional, future-ready homes that stand the test of time. Whether you’re renovating a single room or planning a whole-house update, our design-build team helps you identify and address hidden risks, turning them into lasting solutions.
Ready to stay ahead of costly surprises? Download Redefining Home Maintenance: The Proactive and Essential Guide for Homeowners to learn how to protect your investment, plan with confidence, and keep your home performing at its best.