How moisture travels
Before we can look at consequences and solutions regarding uncontrolled moisture, one must first understand how moisture can invade a home in the first place.
Almost all moisture moves via air currents, but it can also travel through materials and in heat transfer. Air leaks are the biggest culprit of moisture buildup in homes, requiring only a slight pressure difference between two areas to set the problem in motion. This pressure difference occurs much more easily in extreme climates (or seasons) due to major temperature differences between the interior and exterior of a house. The Midwest is no stranger to severe weather patterns.
Identifying and improving humidity in your home
Because water and air both flow in the path of least resistance, water vapor in the air moves almost as freely as the air itself. In the context of a home, the path of least resistance is any gap in solid, sealed material. While it’s not realistic (or healthy) to vacuum seal every centimeter of your house, it is important to prevent air leakage from any unintended space. Here are some common problem areas and solutions to consider as you inspect your home for moisture sources:
While mother nature imposes most issues of moisture control, there are several other possible sources of humidity:
- Air leaks
- As we mentioned, air leaks are the most common source of excess humidity. For more information about air leaks and how to seal them, see our blog “Sealing your Home for Winter.”
- In-home activities involving water vapor
- These include showering, cooking, humidifiers, laundry, and dishwashers.
- Solution: Maintain proper ventilation. Ensure that ventilation is functional, efficient, and installed correctly.
- Evaporation of standing water
- Toilets, pet bowls, and glasses of liquid left out can increase humidity in warm indoor environments. While this source of humidity is far less likely to cause major issues, it’s important to consider all contributing factors.
- Solution: Limit standing water. Cover pots of boiling water and close the lid of the toilet bowl. Again, be sure that ventilation is functional.
- Collected moisture in materials
- The foundational elements of a home can store water within them. Common sites of stored moisture include your home’s foundation, attic, and windows.
- Solution: Check these elements for mold and moisture regularly, and address any problem areas right away. If any part of your home is exposed to flooding, from pipe leaks or natural disasters, clean and dry flooded areas within 24-48 hours or as soon as possible.
Consequences of uncontrolled moisture
Moisture control is crucial to preserving air quality and property value in any space, especially indoors. Without proper maintenance, excess moisture has potential to cause the following concerns:
- Aside from an unpleasant appearance, mold has been shown to exacerbate existing medical conditions and cause respiratory symptoms in otherwise healthy individuals. For example, if you have seasonal allergies, you’re much more likely to have a similar reaction to mold. The same concept raises concern in people with or susceptible to more severe pulmonary conditions like asthma, which have worsened in the presence of mold in several research studies.
- Wood rot
- With prolonged exposure, moisture can cause wood rot—sometimes also called house cancer. Wood rot is a fungus that deteriorates wooden structures and can cause the wood in a home to basically disintegrate, falling apart in sheets, splinters, or dust.
- There are two main types of wood rot: dry rot and wet rot. Wet rot is the primary concern in terms of humidity in the home because it feeds off of moisture and wood alone, potentially creating dangerous structural instability.
- Reduced resale value
- There is no doubt that a home with mold, wood rot, or any other active consequence of excess moisture will be valued lower than a home without these issues. Most home buyers are not willing to inherit a major project unless the price of the property has been reduced well beyond the cost of repairing it, and this is especially true in the context of moisture buildup because of its potential health and safety implications.
- Heftier bills
- Condensation also reduces the R-value of materials, making them less efficient at insulating a house. This quickly leads to higher heating and cooling costs, which adds up after even a few bills. While it may seem bothersome and expensive to address high humidity in your home, the hassle of taking care of any problems sooner rather than later is worth it.
- An invitation for pests
- Small critters depend on easy-to-access water molecules in their living space. Springtails are grey, jumping inspects found in water basins like bathtubs and sinks, usually as a result of failed caulking that leads to pooling water in flooring and walls. Water also attracts termites, whose waste can trigger allergies and other health conditions.
Moisture control, U.S. Department of Energy (not dated)
Facts about Mold and Dampness, Centers for Disease Control and Prevention (September 2017)