Being warm and safe inside your home is comforting when the weather turns cold and snowy. But what if steamy, foggy windows have you feeling like you’re stuck inside a tropical storm? Read on to learn more about wintertime window condensation, when to call an expert, and how to reduce it!

Common causes of window condensation

The main culprit behind wintertime condensation or ‘sweating’ on windows is excess humidity in your home. There are a few things that can spike humidity levels temporarily, such as cooking, showering, and even your home’s heating system, especially if it includes a humidifier.

Other factors that may increase the amount of condensation on windows in winter include new construction or renovation projects. Building materials like wood and plaster contain quite a bit of moisture, which will boost humidity levels in your house particularly during the first few weeks that your furnace kicks in during the colder months. Additionally, modern homes are built ultra-airtight these days, which is great for thermal efficiency, but also means that moisture doesn’t escape the same way it might in an older, less efficient home.


Normal condensation vs. bad condensation

When temperatures start to dip, homeowners may be surprised to see condensation on their new windows in the winter. By and large this is quite normal, but excessive condensation could lead to water damage along window frames, as well as mouldy window sills and, eventually, reduced air quality.

So what causes condensation on new windows in winter anyways? Well, one of the benefits of replacing your home’s windows is that they help increase the overall energy efficiency of your home and reduce the cost of heating and cooling bills. Well-sealed windows with a good insulation value and frames that provide optimal winter window insulation do a great job of keeping cold air out during the winter. They also do a great job of keeping warm, moist air inside your home during the winter.

When warm, moist air meets the cold window surface during winter, it turns into droplets of water. Older, less-insulated windows would allow that warm, moist air to escape, which may mean less condensation, but at the cost of energy efficiency and comfort!

While some condensation is to be expected and can be managed (see tips below), if you see condensation inside the sealed, insulated glass unit of your window, this can mean the seal is failing and you’ll want to consult an expert window installer to troubleshoot the problem.


How to stop condensation on windows in winter

  • Use exhaust fans in high-moisture zones of your home, such as the bathroom fan during baths or showers, and the exhaust fan in your kitchen when you’re cooking.
  • If you live in an older home, upgrading your HVAC (heating and cooling system) or installing a heat recovery ventilator (HRV) will help cycle air in and out of your home more effectively.
  • Try to keep curtains and blinds open when possible to increase air movement around your windows.
  • If you have a humidifier, turn it down during the winter. If humidity in your home is quite difficult to manage, you may want to consider installing a dehumidifer.
  • Move indoor plants away from windows.
  • Don’t air dry clothes after washing.

At Gienow, we stand behind the high-quality products we install and we’re happy to answer any questions you have about replacement window styles or the installation process. If you are currently experiencing issues with Gienow windows, please review our Warranty Page and if you need old windows replaced, please contact our sales team.

Contact Our Sales Team