With the extremely cold weather we are having right now, many homeowners complain about wet or frosted over windows.  A little frost at the bottom of windows is to be expected – when that frost is very thick or covers a large part of the window, your windows are telling you that the house has too much humidity.  Outdoor temperature and indoor humidity should be monitored to prevent both over and under humidification. Amazon.com has many hygrometers to choose from and you can find thermometers with humidity readings in most local stores too.

 As temperates outside drop, it is important to adjust indoor humidity as well to limit condensation.  In small homes or homes with many people living, the house can easily become overhumidified and may require the constant use of bath fans and/or a window cracked open 24/7.  If excessive moisture is building on the windows, it could also be condensing inside the walls, in closets, etc.  That moisture buildup can create damage, both seen and unseen, over time.  I have been in “wet” houses before and can tell you that window damage can just be the start of the problem.  Often I find homes with moisture issues have whole house humidifiers that were set way too high for the conditions.

In larger homes or homes with few people living, the house can get extremely underhumidified due to the dryness caused by the furnace.  In those cases, instead of wet windows you get static electricity shocks and woodwork that shrinks due to the loss of moisture.  A whole house humidifiercan help keep your humidity up in a comfortable range – I suggest the ones that connect to a furnace duct and permanent water supply for ease of use.  Additionally, manufacturers such as Aprilaire are now offering humidifiers with automatic controls that adjust humidity based on outdoor temperature automatically.

Below is the recommended humidity levels for different outdoor temperatures: