Before leaving for vacation, many people search for simple tricks to protect their homes. One viral method suggests placing a sheet of paper and an upside-down glass over a sink drain to block odors and insects. While the idea is based on a real plumbing concept, the method itself is not very reliable.

Every sink and drain has a P-trap, a curved pipe that holds water and creates a barrier between your home and the sewer system. This water seal prevents unpleasant smells, sewer gases, and small insects from entering. The problem begins when a drain sits unused for a long time and the water inside the trap evaporates.

The upside-down glass trick fails because it does not create a true airtight seal. Paper can become wet, break apart, and potentially cause problems, while the glass can easily move and allow odors to escape. It may look like a solution, but it does not protect your plumbing effectively.

A better method is using mineral oil. Pouring a small amount down unused drains creates a layer that floats on top of the water and slows evaporation, helping keep the water seal intact for longer periods. Plastic wrap pressed tightly over a drain or a secure rubber stopper can also provide extra protection.

Not every drain needs special treatment. Short trips usually do not cause problems, but drains that are rarely used—such as guest bathrooms, laundry areas, or basement floor drains—are more likely to dry out.

The best vacation preparation is not complicated. A few simple steps can help keep your home fresh while you are away, giving you peace of mind when you return. The viral glass trick may be popular, but protecting your drains properly is the real solution.