Is your house wet? Is it just damp? Or, more to the point, is it wetter than it should be?
If you have standing water anywhere in your house it’s too wet. That’s pretty easy. A leaking roof, water on the basement (or any) floor, or even standing water in an uncovered sump pit are clear indications that you have a problem. If we could stop here it would be easy, but things get more subtle and sometimes subjective as we drill down to a deeper level.
Your house can be wet in places you can’t see and in ways you aren’t aware of and that can be where the most damage happens. We’ll talk about how it gets wet in a future post. Water can hide in walls and between floors. Sometimes it’s right out in the open and we don’t see it as a problem, a hot tub, an aquarium, or wet laundry hanging in the house. It can even be that long hot shower that causes problems.
We have to worry about water in all its states, liquid, solid and gaseous. Liquid, well that’s just water, we know what that is. Solid is ice. In that form it isn’t as problematic as liquid, but it has a tendency to turn to liquid and that’s a bad thing. Gaseous; steam, water vapor, humidity. Now this is a little trickier. Humidity can cause problems but not as many as liquid water. It can be a great clue as to the presence of water however. And there’s an easy way to measure it.
Inexpensive humidity gauges are available all over the place. They’re combined with digital thermometers and are fairly accurate. You can even get models that can have several remote sensors to monitor conditions in several areas. Depending on how your house is built and configured that can be very helpful.
High humidity can be a very powerful indicator of a water problem. Assuming you keep your house in a normal temperature range, 68F – 75F, your humidity levels should vary from a low in the mid to upper twenty percent range in the coldest days of winter to fifty percent during a hot humid period. If you cool your home during the summer your peak should never exceed 50%, the low 40% range would be better.
We’ll talk about how we came up with these numbers later, and remember that these are only guidelines. Going a bit outside these numbers for brief periods isn’t critical. What’s important is to have a general sense of what’s normal for your house. If you get a sudden change, one way or the other, you want to find out why. If it isn’t weather-related you should get to the bottom of it quickly.
Come back soon. I will be continuing this series of building science posts, hopefully on a more regular basis.