The formation of moisture on windows and doors during extreme Iowa winters is nothing new. However, with record-setting lows this year – and normal daytime highs nearly 50 degrees colder than expected, you may be experiencing additional moisture and even ice formation. Here’s why, and how you can protect your home this winter.

What Causes the Moisture And Ice?

During the winter months, windows and doors tend to be the coldest surfaces in your home. This means when warm, moist air comes into contact with the cold interior surface, the air drops below dew point (between 35 and 40 degrees), leaving moisture on the glass and door handles. It’s the same effect you see on the outside of a drinking glass filled with a cold beverage on a hot summer day. Homeowners may even see the formation of ice this year, with the drastic difference between indoor and outdoor temperatures.

What Can I Do To Prevent Or Get Rid Of Ice And Condensation?

Condensation forming on your home’s windows and doors is typically the result of one or a combination of three factors: humidity, ventilation, and windows. Let’s look at these three areas, and consider ways you can make a few changes to prevent moisture and ice from accumulating:

Proper Ventilation:

  • Check general ventilation: Today’s new construction homes are built using tighter, more efficient construction techniques. This is great for energy efficiency but can restrict ventilation, as natural ventilation to the outdoors is reduced. Wyckoff can inspect your home’s ventilation to ensure it is functioning properly and can advise if additional vents, fans or ventilators are necessary.
  • Utilize exhaust fans and venting: Use bathroom exhaust fans during showers and consider installing exhaust fans in high-moisture areas of your home. Make sure your dryer vents to the outdoors to avoid significant amounts of moisture from staying indoors.
  • Invest in a heat recovery ventilator: Heat recovery ventilators (HRVs) incorporate fan ventilation with a built-in heat exchanger to extract the heat from indoor air before exhausting it outdoors. It then transfers the saved heat to fresh air coming into your home from outside and eliminates any threat of moisture accumulation.
  • Allow air to circulate: Make sure air is allowed to circulate—either passively or mechanically—throughout the entire house. If you close the door to the bedroom, the air can become cold and moist enough to condense on windows.
  • Move air across the glass: Homeowners can often eliminate ice and condensation by utilizing a fan to keep air moving across the glass, and by turning up the heat in the home. When the glass temperature drops below 32 degrees, moisture that is allowed to sit on windows and doors will sit, and in these extreme temperatures, turn to ice more quickly.


  • Avoid thick blinds and window coverings: Putting down thick blinds or excessive window coverings make windows even colder in extreme conditions, as they prevent warm indoor air from reaching the glass. This results in additional condensation and is not advised.
  • Seal and insulate: Bad seals around windows, metal spacers between panes, and inadequate insulation can cause window surfaces to get cold enough for condensation to occur. Make sure seals are secure and insulation is sufficient. If you need to replace windows, opt for triple- or double-pane over single to help eliminate condensation. Or, if you need new windows, but are not yet ready to invest in new, consider movable window insulation, such as foam board outside or plastic film inside.

Home Humidity:

  • Cut back: Moisture from showers, laundry and cooking tends to build up in our homes during the winter causing window condensation, as well as mold and mildew growth. Cut back on long, hot showers when possible and combine loads of laundry to reduce the release of moisture in your home.
  • Check humidity levels: Recommended indoor humidity levels for optimal health and comfort range from 30 to 50 percent. Wyckoff can perform a humidity check on your home with a simple test to ensure your system is achieving adequate humidity throughout.

For more information, contact Wyckoff’s service department at (515) 287-6000.