Frost on inside windows ?


I live in the cold Midwest in a newer home; how do I keep the inside of my windows frost free.

  6 answers
  • If you are in a newer home this should not be happening. What type of windows do you have? Dual pane?

    • Cj Cj on Oct 17, 2018

      The windows are double paned. We’ve covered the windows with plastic shrink wrap last year which helped , but it’s not very attractive.

  • Cindy Cindy on Oct 16, 2018

    Hi Cj. My name is Cindy. You could use a window insulator kit made by 3M. You measure the window and then cut the film to go over the window. Put double-sided tape on the window frame and place film on top of the tape. You can purchase this at your local Home Improvement store or from Amazon. This kit will eliminate drafts and will lower your heating bill.

    • Cj Cj on Oct 17, 2018

      We did this last year and it did help, however we thought a new home shouldn’t have this problem. I’m going to call a HVAC company to determine if a heat exchanger needs to be added to the furnace since if we run the furnace fan constantly the problem is less evident.

  • Mogie Mogie on Oct 16, 2018

    CJ you need to do what you can to prevent frost on the inside of your windows. That can cause damage.

    Use A Dehumidifier

    It seems an excess of humidity is definitely possible, and can be a major contributor to indoor ice. Modern homes are often extremely well-sealed, meaning all of the moisture created by making tea, cooking pasta, taking showers, and exhaling stays within the house and condenses on the cold windows.

    Use Your Exhaust Fans

    Another way to increase ventilation is to operate bath and kitchen exhaust fans part of every day to expel excess" moisture. This is in addition to the time the exhaust fans are used when bathing and cooking. Be sure that exhaust fans blow directly outside and not into attic space.

    Seal All Joints

    A temporary solution may be to carefully seal all the joints of the prime window where the sashes meet the frame with rope caulk, which is removable in the spring.

    Increase The Heat

    Keep your home sufficiently warm, especially at night, to keep frost from forming. It might be worth putting a space heater in a room that is particularly prone to collecting frost on windows to see if that solves the problem.

  • Cj Cj on Oct 17, 2018

    Humidity inside the house was 50% this morning. Three hours ago I turned on the furnace fan to run continuously which reduced humidity to 46%. We have a dehumidifier in the finished basement but I don’t want to use one upstairs because they are noisy and costly to run.

  • Gramie Gramie on Oct 17, 2018

    Mogie is right. The problem is not the windows. It's the humidity in your home. The condensation goes to the coldest surface in the room, but will also take a toll on drywall & furnishings as well. Make sure to use your exhaust when cooking & bathing.

  • Cj Cj on Oct 20, 2018

    You are right. After much research and some common sense physics lessons it does appear the house is too tight, and we can’t remove enough moisture with our conventional furnace. The temperatures here go below zero, thus when the warm moist air contacts the cold two pane windows the water (dew point) is released and freezes on the window. We would need to reduce the humidity to ~20% during our winters. Since moisture comes from the foundation around our home and that we’re in a wet area we will be installing a system to remove moist air from our foundation. It is the same system used for radon remediation. This is an inexpensive first step as we can install this. Next, if that doesn’t remove enough moisture we will need to add a heat recovery system that brings in fresh dry winter air as the combustion air source. I’ve learned that many states require this on a new home-probably because new homes are known to be tight. I liked that I received many good recommendations because they pushed me to research the issue and not jump on one possible solution. Thanks much