Controlling Winter Humidity: A Quick Rule of Thumb

The recent extreme cold weather we experienced in early January was a great reminder to us about the importance of controlling relative humidity. In talking with many of our customers, they were really struggling to understand the concept of “Relative Humidity” and why they were having moisture building up on their windows.

I understand customer concerns about controlling moisture and the potential for mould, and we’ve been working with the building science professionals at Building Knowledge to bring our customers the best possible information on the subject.

We’ve compiled much of what we’ve learned and over the next few blogs I’m going to share some observations to help homeowners optimize their wintertime home comfort. So for starters, think of controlling your home’s indoor humidity as being similar to when you have a shower and need to run the bathroom fan to exhaust the humid air that builds up and fogs the mirror.

And here’s a simple rule of thumb: If you see moisture building up on your windows, you have too much humidity and you need to run your ventilation system.