Older homes carry a lot of character, but they also carry plumbing systems built to standards that are decades out of date. According to the International Association of Certified Home Inspectors, plumbing problems rank among the most common defects discovered during home inspections, and in homes built before the 1980s, the likelihood of finding code violations climbs considerably.
From galvanized pipes corroding from the inside out to water heaters missing required safety valves, many of these issues go undetected until they cause real damage. For homeowners in the Greater Madison area, knowing what to look for can save thousands in emergency repairs and help avoid complications when buying, selling, or remodeling.
Why Older Homes Are More Likely to Have Code Violations
Plumbing codes are updated regularly as the industry learns more about safety, material performance, and water quality. What passed inspection in 1965 or 1975 may now be considered a hazard. Older homes weren’t necessarily built wrong for their time; the standards have moved, and the pipes have not.
This is especially common in Dane County neighborhoods where housing stock dates back several decades. Many of these homes have never had their plumbing professionally assessed since original construction. The violations tend to be quiet: no dripping, no obvious flooding, just slow deterioration happening behind walls and beneath floors.
Many of these code issues also surface during kitchen or bathroom remodeling projects, when older plumbing gets exposed behind walls and under floors. Addressing violations during a planned remodel typically costs far less than repairing them after a failure, which makes a pre-project assessment one of the smarter investments a homeowner can make.
The Most Common Violations RHD Plumbing & Remodeling Finds
Galvanized and Outdated Pipe Materials
Galvanized steel pipes were standard in homes built before 1960. They were coated in zinc to resist corrosion, but that coating breaks down over time. Once it does, the pipes rust from the inside, restricting water flow, discoloring water, and eventually failing. Inspectors flag galvanized and polybutylene pipes regularly, and for good reason. Polybutylene pipes, common from the late 1970s through the early 1990s, have a similar track record. They degrade and crack, often without warning.
If your home still has galvanized or polybutylene supply lines, it’s worth having a licensed plumber assess the system before a small problem becomes a full replacement emergency. RHD Plumbing & Remodeling’s professional plumbing services include pipe condition evaluations and straightforward recommendations on when repair or replacement makes sense.
Improper Drain Slope
Gravity does most of the work in a residential drain system, which is why code requires drain pipes to maintain a specific downward pitch: typically 1/4 inch per foot for pipes three inches in diameter or smaller. When that slope is off, wastewater slows down, solids settle in the line, and clogs become a recurring problem.
In older homes, settling foundations and shifting framing can throw the pipe slope out of alignment over time, even if it was installed correctly. A drain that’s sluggish or frequently backing up may point to a slope issue worth investigating.
Missing or Improperly Installed Trap Configurations
Every drain in a home needs a properly installed P-trap: the curved pipe section that holds a small amount of water to block sewer gases from rising back into living spaces. Older homes with DIY plumbing added over the years sometimes have S-trap configurations instead. S-traps were common before modern venting requirements, but they can siphon the water seal out of the trap, letting sewer gas in.
Sewer gas isn’t just unpleasant. It contains methane and hydrogen sulfide, both of which are health hazards at sufficient concentrations. If your bathroom or laundry room has unexplained odors, a trap issue could be the source. RHD Plumbing & Remodeling’s bathroom remodeling experts frequently uncover these problems during fixture upgrades and address them as part of the project.
Missing or Inaccessible Cleanouts
Plumbing codes require cleanouts at certain points in the drain system so plumbers can remove blockages quickly without opening walls or digging up your yard. They need to be placed at accessible locations and at specified intervals along longer runs.
In many older homes, cleanouts are either missing entirely, installed behind drywall that was later finished over, or blocked by years of landscaping and hardscaping. When a blockage hits and there’s no accessible cleanout, the repair gets significantly more invasive and expensive. It’s a straightforward issue to fix proactively, and a costly one to discover during a plumbing emergency.
Water Heater Code Issues
Water heater requirements have evolved substantially over the years. Current code mandates a temperature and pressure relief (T&P) valve on all tank water heaters, proper venting for gas units, and safe clearances from combustible materials. Older units, particularly those installed by previous homeowners without permits, frequently fall short on one or more of these requirements.
A T&P valve that’s been capped or removed is one of the more serious violations RHD Plumbing & Remodeling plumbers encounter. That valve exists to prevent dangerous pressure buildup inside the tank. If your water heater is more than 10 years old or was installed without a permit, an inspection is a smart step. RHD offers free consultations on water heater installation and replacement to help homeowners understand exactly where they stand.
Shut-Off Valve Problems
Every fixture in a home should have an accessible, functional shut-off valve. Kitchen sinks, toilets, washing machines, outdoor hose bibs: all of them. Code violations occur when valves are absent, seized shut from years of disuse, or enclosed behind finished walls without an access panel.
This is an issue that seems minor until a pipe bursts or a fixture fails, and there’s no way to stop the water without shutting off the entire house. In older homes, it’s common to find only a single main shut-off valve with no individual fixture controls at all.
Improper Venting
Every drain in a home needs air to flow properly. Venting allows air into the drain system so wastewater can move freely without creating pressure vacuums that slow drainage or pull water out of traps. Flat venting (where a vent pipe runs horizontally without proper pitch) and completely unvented drains are both code violations that show up regularly in older plumbing systems.
Signs of improper venting include gurgling sounds after flushing, slow drains throughout the house, and persistent sewer odors with no obvious source.
What Happens If You Ignore These Issues?
Most plumbing code violations don’t announce themselves. They build slowly: a corroded pipe developing a pinhole leak inside a wall, a faulty water heater missing a required safety valve, a seized shut-off that becomes useless in an emergency. The longer these issues go unaddressed, the more expensive the fix tends to be; they are also more likely to complicate a home sale or remodel down the line.
Dane County homeowners planning a bathroom remodel or kitchen update should know that permit pulls often trigger inspections that surface existing violations. Finding and addressing them proactively (before a project kicks off) puts you in a much better position than discovering them mid-construction when timelines and budgets are already committed.
Get Ahead of Code Issues With RHD Plumbing & Remodeling
If you live in an older home in Dane County and want to know whether your plumbing system meets modern standards, schedule an inspection with RHD Plumbing & Remodeling today. Our licensed plumbers can identify hidden code issues and recommend practical solutions before they turn into costly emergencies.
As a locally owned, women-led company serving the Greater Madison area since 2006, RHD Plumbing & Remodeling combines experienced service plumbers with a full remodeling team under one roof. Our 24/7 Dream Team can respond quickly when plumbing problems turn urgent, and our large local service fleet lets us reach homeowners across Dane County efficiently. Free estimates are available, and we offer financing up to $100,000 for larger projects.
Contact us to schedule a walkthrough or learn more about RHD and what sets our team apart.