The Surprising Benefits of Placing a Salt Bowl by Your Windows: A Unique Perspective on Home Economics

Dealing with Condensation During Cold Months

During the chilly months, many individuals face a common yet annoying issue: condensation on windows.
This occurrence arises when warm, humid air comes into contact with a cold surface like glass, leading to the formation of small water droplets.
According to the National Oceanic and Atmospheric Administration (NOAA), condensation is not merely a matter of temperature, but rather the difference between the air temperature and the dew point.
The dew point is the temperature at which air can no longer hold moisture and begins to condense.

If left unaddressed, this accumulation of condensation can result in various problems, such as excess humidity and mold, damaging window frames and potentially posing health risks.
In vehicles, this issue can be managed through the air conditioning system, which helps reduce internal humidity.
However, at home, where forced ventilation systems may not be available, tackling the issue can become more complex.

The Salt Experiment

A simple, low-cost, and popular solution is to place a bowl of salt near the window.
According to expert Andy Ellis on IFLscience.com, salt naturally possesses properties that enable it to absorb moisture from the air, effectively reducing condensation on glass surfaces.
To implement this method, one merely needs to fill a small bowl or jar with table salt or rock salt, adjusting the quantity based on the window size.

This solution is not only economical but also requires minimal effort: filling a bowl and placing it on the windowsill is all it takes.
It’s worth noting that salt begins absorbing water vapor only at certain humidity levels.
Nevertheless, in particularly humid homes, it can still be useful in controlling the situation.

How the Hygroscopic Behavior of Salt Works

The ability of salt to absorb moisture is linked to its unique property known as “hygroscopic behavior,” as explained by chemical engineer John Francis Richardson.
Deliquescence is a process wherein solids, such as inorganic salts (e.g., calcium chloride), absorb water vapor from the air until they dissolve into a saturated saline solution.
When the vapor pressure in the environment is high, salt can absorb moisture, and at critical levels, it dissolves.
However, if the home’s humidity level is lower, the salt’s effectiveness diminishes.
A study by the German transport information service found that salt significantly absorbs moisture only when relative humidity exceeds 74% at 20°C.
Most homes, however, experience humidity levels between 30% and 60%, meaning only those with humidity above 70% might witness meaningful results from using salt.

Alternative Methods to Reduce Humidity

While salt can help reduce condensation in the more humid areas of the home, such as kitchens and bathrooms, it is not a definitive solution.
Ventilation remains the most effective method: opening windows for just a few minutes allows humid air to escape, reducing condensation accumulation.
Modern windows often come equipped with integrated air vents that facilitate this process, enhancing air exchange without the need to leave a window wide open.

Ultimately, placing a bowl of salt near windows is a simple trick that may offer a small benefit in alleviating excess humidity in homes experiencing condensation issues.
However, for lasting effects, regular ventilation and the use of dehumidifiers remain the most effective options.
For those living in particularly humid environments, salt can serve as an economical ally, but it is essential to recognize that it acts more as a temporary support than a permanent solution.