If you own rental property long enough, you’re going to get a text at 10 PM about water coming through a ceiling. It’s not a matter of if—it’s when. Plumbing issues are consistently one of the top maintenance expenses for small landlords, and the worst ones always seem to happen on holidays.
The good news: most plumbing disasters are predictable. The same handful of problems show up over and over, and almost all of them are preventable with basic habits and a little proactive maintenance. Here’s what you’ll actually encounter and what to do about it.
1. Clogged Drains and Backed-Up Toilets
This is the single most common plumbing call you’ll get. Kitchen sinks clogged with grease, bathroom drains choked with hair, and toilets jammed with things that should never have been flushed.
How to prevent it
- Install drain screens in every shower and bathroom sink. They cost about $3 each and save you hundreds in drain-clearing calls.
- Include a “what not to flush” clause in your lease. Spell it out: no wipes (even “flushable” ones), no feminine hygiene products, no cotton swabs. Tenants don’t always know this stuff.
- Skip the garbage disposal in rentals if you can. Disposals give tenants a false sense of security about what can go down the drain. If you do have one, educate tenants about grease, fibrous foods, and coffee grounds.
- Schedule a preventive drain cleaning every 1–2 years, especially in older buildings. A plumber can snake the main lines for $150–$300, which is a fraction of what an emergency backup costs.
2. Running Toilets
A running toilet can waste 200+ gallons of water per day. If you’re paying the water bill, that’s money literally going down the drain. Even if tenants pay water, a running toilet can escalate into a more expensive repair if the internals wear out completely.
How to prevent it
- Replace flapper valves proactively. They degrade every 3–5 years. A flapper costs $5 and takes ten minutes to swap. Do it at every turnover.
- Upgrade to fill valves with adjustable float cups instead of the old ball-and-arm style. They’re more reliable and easier to adjust.
- Ask tenants to report running toilets immediately. Some tenants will jiggle the handle for months and never tell you. Make it clear in your move-in walkthrough that this is a quick, free fix—they just need to let you know.
3. Leaking Faucets and Fixtures
A slow drip doesn’t feel urgent until you see the water bill or notice the staining and mineral damage around the fixture. Leaky faucets also train tenants to ignore water problems, which can bite you later when something bigger starts leaking.
How to prevent it
- Install quality faucets from the start. You don’t need the most expensive option, but avoid the cheapest big-box models. Moen and Delta both make solid, affordable lines with good cartridge availability—important for future repairs.
- Replace washers and cartridges at turnover. If a faucet has been in use for 3+ years, swap the cartridge. It takes 15 minutes and costs $10–$20 in parts.
- Check under every sink during seasonal inspections. Look for moisture, discoloration, or warped cabinet floors. Slow leaks under sinks cause mold and wood damage that gets expensive fast.
4. Water Heater Failures
Tank water heaters have a lifespan of 8–12 years, and when they fail, they often fail dramatically—flooding basements, utility closets, or worse. A 40-gallon tank releasing its contents into a finished space is a cleanup you don’t want to deal with.
How to prevent it
- Know the age of every water heater you own. The serial number contains the manufacture date (look up the format for your brand). If it’s past 10 years, start budgeting for replacement.
- Flush the tank annually to remove sediment buildup. This extends the heater’s life and maintains efficiency. It takes 20 minutes with a garden hose.
- Install a drip pan and drain line under every tank water heater, especially if it’s on an upper floor. This gives you a margin of safety when things go wrong.
- Test the temperature and pressure (T&P) relief valve once a year. If it doesn’t release water when you lift the lever, replace it immediately—a failed T&P valve is a safety hazard.
5. Frozen and Burst Pipes
If you own property in a climate that sees freezing temperatures, this is the big one. A burst pipe can dump hundreds of gallons of water into your property in minutes, causing tens of thousands of dollars in damage.
How to prevent it
- Insulate all exposed pipes in unheated spaces—basements, crawl spaces, garages, and exterior walls. Foam pipe insulation is cheap and easy to install.
- Add a lease clause about winter precautions. Require tenants to keep the heat at a minimum of 55°F, even when away. Spell out that they should open cabinet doors under sinks on exterior walls during cold snaps.
- Install smart leak sensors near water heaters, washing machines, and under sinks. Basic Wi-Fi sensors cost $20–$30 each and send alerts to your phone. They won’t prevent a burst, but they dramatically reduce damage by giving you early warning.
- Know where every shutoff valve is in every property, and make sure they actually work. Test them annually. A seized shutoff valve during a pipe burst turns a bad situation into a catastrophe.
Track It So You Can Stay Ahead of It
The pattern here is obvious: most plumbing disasters come from deferred maintenance and lack of documentation. If you don’t know when the water heater was installed, when the drains were last cleaned, or which unit has the old supply lines, you’re always reacting instead of preventing.
Keep records of every maintenance request, every repair, and every appliance age. When you can see the history of a property at a glance, you make better decisions about where to spend money before something breaks. Create a free DoorLedgers account to start tracking maintenance, expenses, and property details in one place—so the next plumbing issue is a minor fix, not a midnight emergency.