The proposed trick involves removing the shower drain cover, cutting both ends off a balloon, and stretching the remaining band around the cover’s edge or underside. In theory, this makeshift gasket narrows gaps that cockroaches might squeeze through. However, it is not a proven pest-control solution, and its usefulness depends on the drain’s design. It will not necessarily block the cover’s drainage holes, and loose material must never be allowed to fall into the pipe.

If you try it, keep water openings clear and check frequently for trapped hair, shifting rubber, or slower drainage. Remove the band immediately if water pools. A properly fitted drain screen is generally a more dependable physical barrier. Lasting prevention also means fixing leaks, cleaning away residue, sealing gaps around pipes, and keeping infrequently used drain traps filled with water. If roaches keep appearing, a pest professional or plumber can help identify the actual entry point.