4 Ways Fluctuating Humidity Levels Can Impact Your Home, According to HVAC Pros

We’re currently in the midst of the seasons changing, so some days may be warmer than others, causing humidity levels to fluctuate in our own homes. Josh Mitchell, an HVAC technician and owner of AirConditionerLab, recommends always maintaining the right humidity level in your own home

We spoke with HVAC and home reno experts to share how different humidity levels can impact your home and what you need to look out for.

Wood Expansion and Shrinking

Since wood absorbs moisture when humidity is high and dries out when it’s low, this constant cycle can cause cracking, warping, and gaps in hardwood floors and furniture, Mitchell says.

“A sudden drop in humidity can also make wood brittle and more prone to breakage,” Mitchell explains.

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Condensation and Mold Growth

Marc Jiggins, the managing director at Pyramid Eco, explains how too much moisture will lead to condensation, which can cause mold growth and damage to your woodwork.

Mitchell agrees and says that during colder months, condensation on windows and walls can signal excessive indoor humidity.

“This moisture can seep into walls and insulation, leading to mold and mildew growth,” Mitchell says. “If left unchecked, mold remediation can cost anywhere from $500 to $6,000.”

Damaged Paint

If you’ve been noticing cracked or peeled painted walls, it may be time to re-evaluate your humidity levels.

Mitchell explains that paint and caulk can crack since low humidity pulls moisture from the walls. In some extreme cases, drywall can also start crumbling so keep an extra eye out for brittle drywall.

Higher Electrical Bills

According to Mitchell, most homeowners crank up their AC systems to make them cooler when there are higher humidity levels, which can automatically increase electrical bills.

“This can increase energy costs by 5-15% annually,” Mitchell says.

Tips for Maintaining Balances Humidity Levels

• Invest in a hygrometer. A simple hygrometer can range from $10 to $30 but will be worth the cost since it tracks humidity levels ahead of time so you can make adjustments accordingly, Mitchell says.
• Adjust HVAC settings. Mitchell recommends running the fan on “auto” instead of just “on” since it will remove any excess moisture.
• Seal any air leaks. Small cracks around doors, windows, and crawl spaces can instantly let moisture inside. Mitchell suggests using weather stripping or caulking to further reduce drafts and stabilize the humidity.