Here’s why you should always leave an upturned glass and a piece of paper in the sink before going on vacation

The Importance of This Trick

Leaving an upside‑down glass on a piece of paper in your kitchen sink before you head out on a trip may sound like a quirky superstition, but it’s actually a low‑tech safeguard that can spare you a costly repair or a nasty surprise when you return home. The sink is a hub of plumbing activity, constantly exposed to water, food particles, and the occasional stray object. When a house sits idle for days or weeks, the water that remains in the pipes can stagnate, encouraging mineral buildup, bacterial growth, or even tiny blockages that expand while you’re away. By placing a simple glass upside down, you create a tiny air pocket that helps keep the drain line from sealing shut completely, while the paper absorbs any stray drips that might otherwise pool and create a damp environment for mold.

In practice, this trick works as a passive “drain guard.” The glass’s rim blocks larger debris from entering the pipe, and the paper catches any moisture that might escape from a leaky faucet or a slow‑draining sink. When you walk back into your kitchen after a week or two, you’ll find the sink dry, the drain clear, and the glass sitting neatly on a dry sheet of paper—an immediate visual cue that nothing went wrong while you were away.

Prep time: 2 minutes. Cook or resting time: None. Makes: One sink protection setup per household.

How It Prevents Sink Issues

The primary way the upside‑down glass helps is by maintaining a small amount of air at the drain opening. When a sink is completely empty, the water in the P‑trap can evaporate, leaving the trap dry. A dry trap loses its seal against sewer gases, which can travel up the pipe and release unpleasant odors into your home. The glass, sitting upside down, keeps the trap partially filled with air, reducing the chance of a full vacuum that would draw gases upward.

Additionally, the paper underneath serves as a moisture‑absorbing buffer. If a faucet leaks slowly, or if condensation forms on the sink walls, the paper will soak up the water before it can accumulate and cause rust or mildew on the metal basin. This is especially useful in humid climates where condensation can be more pronounced.

Finally, the glass acts as a physical barrier to larger particles—like a stray piece of food or a small utensil—that might otherwise fall into the drain while you’re not there to notice. By catching these items, the glass reduces the risk of a future clog that could require a plumber’s intervention.

Why It's Recommended by Professionals

Plumbers and home‑maintenance experts often stress the importance of “air breaks” in drainage systems. An air break is essentially a small pocket of air that prevents the formation of a complete vacuum, which can otherwise cause the water in the trap to be sucked out. Many professionals suggest leaving a small amount of water in the trap or using a sink plug, but the upside‑down glass method is a cleaner, mess‑free alternative that doesn’t require you to remember to refill the trap later.

Furthermore, home‑inspection specialists recommend visual cues for quick checks. When you return, the presence of the glass and the dry paper tells you at a glance that the sink has remained dry and that no unexpected leaks occurred. This aligns with the “first‑look” inspection routine that experts use to spot problems early, before they become expensive repairs.

Insurance adjusters also appreciate preventative measures. Some policies may offer discounts or lower premiums for homeowners who can demonstrate routine maintenance practices, and this simple trick can be part of that documented care regimen.

Simple, Fast, and Free

All you need is a clean glass—any size works, though a medium drinking glass is ideal—and a sheet of paper, such as a kitchen towel or a piece of printer paper. No special tools, chemicals, or purchases are required. The entire setup takes less than two minutes, making it perfect for the last‑minute checklist before you lock the front door.

The cost‑free nature of this tip is a major advantage. Unlike installing a backwater valve or hiring a plumber for a pre‑vacation inspection, you can implement this safeguard with items you already have in the kitchen. This makes it accessible for renters, homeowners, and anyone on a budget who still wants to protect their plumbing.

Because the method is so easy, it’s easy to forget to do it—so consider adding it to your vacation packing list or setting a phone reminder. Once it becomes a habit, you’ll never have to worry about a clogged or smelly sink after a trip.

Common Sink Problems While on Vacation

When a house sits idle, several issues can arise in the kitchen sink:

• Dry P‑trap: Evaporation of the water seal can allow sewer gases to seep into the home, creating a foul smell.
• Clog formation: Food particles, grease, or small objects can settle in the drain, hardening over time and causing blockages.
• Leakage: A slow leak from a faucet or a cracked pipe can go unnoticed, leading to water damage or mold growth.
• Mildew and mold: Persistent moisture on the sink surface or in the cabinet can foster fungal growth, especially in humid climates.
• Rust: Metal components exposed to standing water may rust, especially if the sink is made of stainless steel with a lower grade finish.

Each of these problems can be mitigated by the simple glass‑and‑paper setup. The glass helps keep the trap sealed, the paper absorbs stray water, and the visual cue alerts you to any unexpected moisture.

How to Set It Up

1. Choose a clean glass. Any glass will do, but a sturdy, wide‑rimmed drinking glass is ideal because it sits flat when upside down and won’t tip over easily. Make sure it’s free of cracks or chips that could cause it to break.
2. Place a sheet of paper in the sink. Use a kitchen towel, a piece of parchment, or a sheet of printer paper. Lay it flat on the basin so it covers the area where water might collect.
3. Turn the glass upside down. Position the glass so its open rim faces the sink basin, and its base rests on the paper. The glass should be stable; if it wobbles, adjust the paper or choose a heavier glass.
4. Check for drips. Before you leave, run the faucet briefly and watch the paper. If any water lands on the paper, wipe it away with a towel and ensure the faucet is fully turned off. The goal is a dry paper surface.
5. Leave the sink untouched. Do not run the dishwasher or use the sink while you’re away, as this could interfere with the setup. The glass and paper will remain in place, acting as a passive guard.
6. Document the setup. Take a quick photo of the glass on the paper. When you return, you can compare the photo to the current state to see if anything changed.

Other Vacation Prep Tips

While the upside‑down glass protects your sink, consider pairing it with other simple steps to ensure a smooth return home:

Unplug appliances. Disconnect refrigerators, coffee makers, and other electronics to prevent power surges and reduce energy consumption. If you have a smart fridge, set it to “vacation mode” to keep it running at a lower temperature.

Turn off the main water valve. This is a more comprehensive safeguard than just the sink. Shutting off the main supply prevents any burst pipes or leaks from causing water damage while you’re away.

Set your thermostat. In colder climates, set the thermostat to a low but safe temperature (around 55 °F/13 °C) to avoid frozen pipes. In hot climates, raise the thermostat a few degrees to save energy while keeping the house from overheating.

Secure windows and doors. Check that all windows are closed and locked, and consider using a temporary lock or security bar for added protection. A simple window sensor can alert you to any unexpected opening.

Leave a light on a timer. Simulating occupancy can deter burglars. Set a timer to turn lights on and off in different rooms at varying intervals.

Notify a neighbor. Ask a trusted neighbor to check your mail and look for any signs of trouble. They can also alert you if they notice a leak or unusual activity.

Closing the Kitchen Before You Go

Before you lock the front door, give your kitchen a quick once‑over. Wipe down counters, empty the trash, and make sure the dishwasher is empty and dry. Place the upside‑down glass on a dry sheet of paper in the sink, double‑check that the faucet is fully off, and ensure the main water valve is closed if you have the option. By taking these few minutes, you’ll return to a kitchen that feels exactly as you left it—clean, dry, and ready for your next culinary adventure. The peace of mind you gain from avoiding a clogged or smelly sink is well worth the tiny effort, and it lets you focus on the fun parts of your vacation instead of worrying about home maintenance.