Thankfully, our winter here in Calgary has been quite mild up until recently. Then this whole polar vortex thing decided it was going to come along and ruin a few weeks outside for us. But let’s not let this weather sneak in and ruin our homes as well.


This weather can wreak absolute havoc on our homes if we aren’t careful; inside, outside, you name it, we need to stay on top of it. There are a few maintenance tips that are quite common: hose bibs, weatherstripping, etc. I won’t dive into that as there is a plethora of easily accessible information readily available with a quick google search.


I’m going to chat more about some less known issues that have the potential to create some fairly costly repairs. On the other hand,  addressing these same problem areas properly can make your home more comfortable during these wicked cold snaps.


Okay, here is the MOST common thing I see in homes when it gets cold; frost on the inside of  windows. This is much harder to avoid with an older window, in which case it may be time to schedule a window replacement. But for a new, double/triple pane sealed window, this should not happen and can be avoided.


The cause of this issue is condensation. We like our houses to feel warm and humid, so we crank our heat to 22 and run humidifiers to accomplish that. When that hot, humid air meets a cold surface, such as a pane of glass, the air cools and can no longer hold as much moisture. This causes moisture to condense on the glass and, in very cold scenarios, it starts to freeze on the surface. This leaves you with a nice frosty window. Keep in mind, this can happen anywhere that the house is improperly sealed: baseboards, exterior corners, skylights, etc.


The real problems start to occur when this frost starts to melt. This can cause millwork to swell, paint to crack, mold to grow…. the list goes on. So, the key is to eliminate the possibility of condensation developing in the first place. This is a fairly simply goal to accomplish when armed with the proper information. So let’s get started on the most common causes of this, and the best ways to mitigate each cause:

  • Ventilation. A lack of airflow will force stagnant air to sit in front of a colder surface on an exterior wall. This will increase the likelihood of condensation as the air begins to cool. This problem can be solved by ensuring all heat vents are open in front of exterior penetrations, such as windows and doors. Another good habit is to keep your furnace fan running continuously, as opposed to only when it’s actively heating. Running the furnace fan cycles air throughout your home which minimizes stagnant air, as well as thermal stacking.
  • Humidifiers. Here is a simple one, turn it down. Your home’s humidity level needs to decrease with the outside temperature. See below for a rough guideline on where you should keep it set.

  • Window coverings. Window coverings can be a potential issue because they often create a pocket of stagnant air against your exterior walls. Try and leave window coverings open as often as possible to allow air in your home to pass over the windows. This will prevent trapped air from cooling and creating condensation.


If you notice other areas in your home that have a frost or moisture build up in these cold temperatures, it could be a sign that you have a deficiency in your exterior envelope or insulation, and should be addressed as soon as possible. This could be anything from a hole in your wall’s vapour barrier, to a void in your insulation. A thermal camera can very quickly diagnose the problem.