Window Condensation – A Simple Problem?

Not always true and might be diagnosed using Absolute Humidity.

In our homes we can easily blame window condensation on a number of things (sometimes all done at the same time!).

  • Boiling a big pot of water for a batch of spaghetti on the coldest day of the year.
  • A good hot shower without running an exhaust fan.
  • A laundry dryer vent not venting very well to the outside.
  • Even new homes may experience condensation as a result of higher moisture content in fresh building materials.

Here is an interesting page from the “Chicago Window Expert” explaining why Relative Humidity isn’t simply the only explanation for condensation problems.

The following chart can be used as a guideline which many of us have seen somewhere before.

humidity level chart

Some easy remedies may include cracking a window to let out some humidity or running that exhaust fan. When outdoor temperatures reach cold and REALLY cold adjust humidity accordingly. The new home with fresh building material problem is a little tougher. Follow builders’ recommendations… you do not want your new home drying out too fast!

If condensation seems to be on the inside of the glass there is likely a seal failure which can require unit repair. This happens more on windows that are exposed to temperature extremes. Windows in the sun most of the day followed by a chilly night can take a toll over time.