Before going on vacation, most people focus on locking doors, unplugging electronics, and protecting valuables. However, one small area often gets forgotten: the sink. Both kitchen and bathroom drains can create problems when a home sits unused for days or weeks, especially during warmer seasons.

When plumbing is not used regularly, the water inside drain traps can dry out, allowing unpleasant sewer odors to enter the house. The damp, quiet environment can also attract insects such as gnats, ants, and cockroaches that may travel through pipes searching for moisture. Fortunately, preventing these issues does not require expensive products or complicated solutions. A simple household trick can create a protective barrier while you are away.

The idea is surprisingly simple.

Before leaving, clean the sink thoroughly and make sure there is no food residue, grease, hair, or standing water around the drain. Then place a piece of paper or a thin sheet of material over the drain area and position an upside-down glass over it.

At first, the setup may seem almost pointless. After all, how could an ordinary glass and piece of paper protect a sink?

The trick is mainly about creating a visible barrier and making it easier to notice changes while you are away. The covered drain can discourage insects from accessing the open area of the sink, while the paper can also provide a simple indicator if moisture, insects, or other activity occurs.

However, the most important protection is still the plumbing itself.

Most household sinks have a curved section of pipe beneath the drain called a trap. This section normally holds a small amount of water. That water acts as a barrier between the interior of the home and the drainage system, helping prevent sewer gases and odors from traveling back through the pipe.

When a sink is used regularly, fresh water continually replenishes the trap. But during a long vacation, several days or weeks may pass without anyone turning on the faucet. Depending on conditions, some of the water can evaporate.

Once the water seal becomes weak or disappears, unpleasant odors may enter the home.

This is why simply covering the top of the sink is not a complete solution. If you are leaving for an extended period, maintaining the water seal is more important than the glass itself.

One simple approach is to run water into each sink shortly before leaving so the traps are filled. The same principle applies to other plumbing fixtures, including showers, bathtubs, and floor drains.

If a property will remain vacant for a particularly long time, homeowners may also want to consider appropriate methods for protecting drain traps from evaporation. The correct approach can depend on the plumbing system and local recommendations, so it is worth checking with a qualified plumber if the home will be empty for an extended period.

The kitchen sink deserves special attention because even tiny amounts of food residue can become unpleasant when left untouched. Before leaving, clean the basin and remove crumbs, grease, and anything else that could attract insects.

The garbage disposal, if you have one, should also be cleaned according to the manufacturer’s instructions.

Bathroom sinks can present a different problem. Toothpaste residue, hair, soap, and moisture can accumulate around the drain. Cleaning these areas before a trip can reduce the chances of returning to an unpleasant surprise.

The upturned glass also has a practical advantage: it reminds you that the sink has been prepared for your absence.

Travel preparation can become hectic. People often check passports, luggage, windows, doors, appliances, and security systems while rushing to leave. Small tasks are easy to forget.

Having a simple visual setup in the sink can serve as a final reminder that the plumbing has been checked.

There is another reason to avoid leaving standing water around the sink itself.

Water that remains on surfaces can evaporate and contribute to a humid environment. In warm conditions, stagnant moisture may encourage the growth of unpleasant odors or microorganisms. Wiping the sink dry before leaving can therefore be a useful final step.

The same principle applies throughout the bathroom.

Dry wet towels, wipe down damp surfaces, and make sure there are no obvious sources of standing water. If you have a shower curtain, allowing the area to dry before leaving can also help keep the bathroom fresher.

And don’t forget the toilet.

The toilet’s built-in water trap also helps block sewer gases. If a house will be empty for a long time, evaporation can eventually affect the water level. For extended absences, homeowners may want to seek plumbing-specific advice about maintaining traps rather than relying solely on a covering placed over the bowl.

The key lesson is that there is no single magic vacation trick.

An upturned glass and piece of paper can be a useful household reminder and a simple physical barrier around a sink, but they should not be treated as a substitute for proper plumbing maintenance.

Before leaving, think about what your home will be like while nobody is using it.

No faucets will be running.

No one will be flushing toilets.

No one will be cleaning crumbs from the kitchen.

No one will notice a small leak immediately.

And no one will be opening windows or ventilating rooms as part of their normal routine.

That is why a few minutes of preparation can make returning home much more pleasant.

Clean the sinks. Remove food residue. Dry wet surfaces. Check for leaks. Run water through fixtures to replenish traps. Make sure doors and windows are secure, and consider appropriate measures for any plumbing fixtures that may remain unused for a long period.

Then, if you like the simple glass-and-paper method, place the barrier over the sink as a final reminder.

When you return from vacation, remove the glass and paper, inspect the sink, and run fresh water through the drain.

If you notice persistent sewer smells, unusually low water levels, slow drainage, insects, or signs of leakage, don’t simply ignore them. Those symptoms can indicate a plumbing or moisture problem that deserves attention.

The biggest benefit of this little routine isn’t that a glass can magically protect your entire plumbing system. It is that it encourages you to think about an easily forgotten part of the house before leaving.

A vacation should be about relaxing, not coming home to strange odors, unexpected insects, or plumbing surprises.

So before you close the front door and head to the airport, take one final walk through the house.

Check the sinks.

Check the drains.

Check for standing water.

And make sure your plumbing will be ready for the time when you return.