Seasonal Humidity Control Tips for Missouri Homes

From humid summers to dry winters, Missouri’s seasonal changes can wreak havoc on your indoor air quality and home health. Without proper humidity control, you risk mold growth, warped flooring, respiratory issues, and even HVAC inefficiency.

At Purisync Heating and Air, we help homeowners across Kirkwood and nearby areas control indoor moisture year-round. Here’s your seasonal guide to keeping humidity in the healthy range — and your home protected.

What’s the Ideal Indoor Humidity?

The recommended indoor humidity level is between 30% and 50%. Levels above 60% increase the risk of mold, while anything below 30% can lead to dry skin, static, and damaged wood surfaces.

Spring: Manage Rising Moisture

• Use a dehumidifier in basements and crawl spaces
• Check for leaks after winter snow melt and rainstorms
• Clean and service HVAC systems before cooling season
• Seal windows and doors to prevent humid outdoor air from entering

Summer: Reduce Excess Humidity

• Run bathroom and kitchen exhaust fans during showers and cooking
• Install a whole-house dehumidifier if levels stay high
• Set your AC to “Auto” mode (not “On”) to allow moisture removal
• Check for condensation on windows or cold water pipes

Fall: Prepare for Humid Air and Temperature Drops

• Test your sump pump before fall rains (see our sump pump guide)
• Inspect attic and roof for signs of trapped humidity
• Maintain proper airflow with clean vents and filters

Winter: Add Moisture Safely

• If indoor air feels dry, use a humidifier — but keep it under 50%
• Avoid over-humidifying rooms with poor ventilation
• Check for ice damming, which can lead to roof leaks and hidden mold

Bonus: Use a Hygrometer to Monitor Humidity

A simple indoor humidity monitor (hygrometer) helps you track levels room-by-room. Smart models can connect to your phone or HVAC system for real-time alerts.

Warning Signs of Poor Humidity Control

• Mold smell or growth in bathrooms, basements, or near windows
• Warped wood floors, cabinets, or baseboards
• Peeling paint or bubbling wallpaper
• Increased allergy symptoms indoors

Get Year-Round Moisture Protection in Missouri

Purisync offers inspections and humidity solutions for homes in:

• Crestwood
• Affton
• Webster Groves
• Town and Country

Call (314) 338-5111 or schedule a humidity assessment today to keep your home healthy through every season.