When to be Concerned About Condensation on Windows

Condensation is common in households due to excess humidity or water vapor in the air. When water vapor comes into contact with cold surfaces such as windows or mirrors, it turns into water droplets that create a foggy appearance. While household condensation is normal, excessive condensation can potentially cause damage to your home. Keep reading to gain a better understanding of common household condensation to know when to take action. 

Normal Levels of Condensation

It’s typical to experience condensation at the start of winter as your heating system begins to dry out any moisture absorbed in summer. However, condensation should reduce after your home has been heated for a couple of weeks. Homeowners may also notice increased condensation after installing energy-efficient replacement windows. The tighter seal helps prevent excess moisture from escaping, resulting in common household condensation.

Contributing to Indoor Humidity 

Anything that involves water will add humidity to the air in your home. Everyday household practices such as cooking, showering, doing laundry, mopping and using a humidifier can increase humidity levels.  

Cause for Concern

Excessive window condensation is one of the first signs the humidity level in your home is too high. While window condensation will likely be the first thing you notice, it will often be accompanied by frost, peeling paint, and moisture spots on the ceilings and walls. These are all indicators you have too much humidity in your home.

Ways to Reduce Condensation

The best way to reduce common household condensation is to eliminate excessive humidity. You can lower household humidity levels with the following methods: 

  1. Install proper ventilation and exhaust fans in the kitchen, bathroom and laundry room to circulate and remove humid air. 
  2. Open up the windows for a few minutes each day to let the fresh dry air in and moist air out. Limiting the time will help ensure minimal impact on your heating efficiency. 
  3. Ensure that attic and basement vents are open and properly sized for the space. 
  4. Open your fireplace dampers to let excess air escape. 
  5. Restrict indoor plants to one area and try not to overwater. 


If excess condensation persists, consult a professional heating contractor or qualified expert.