The Purpose of the Hole in Your Sink
Have you noticed the hole near the top of your bathroom sink? Depending on its design, your sink may have one to three holes that serve two main purposes: allowing air to escape the drain and preventing overflow when the stopper is engaged.
Without this hole, a full basin would drain slowly due to air resistance. The overflow hole ensures proper airflow, maintaining the drain’s efficiency.
You might see that kitchen sinks often lack this hole, while bathtubs have one. Bathtubs can fill quickly, so the overflow hole acts as a safety measure. In kitchens, the divider between basins helps manage overflow by allowing air to escape.
Additionally, kitchen sinks avoid overflow holes due to hygiene concerns; bacteria can thrive in these openings and potentially contaminate food or utensils.