How to Easily Check if Your Home’s Humidity is Too High or Too Low


Checking your home’s humidity might sound like a daunting task, but it’s actually a whole lot easier than you might be thinking!

Besides obvious signs that you can see or smell, there are actually a few different ways you can test it as well!

Now, what are the obvious signs that I’m talking about that you can look for? Here’s a list.

Signs of high humidity in your home:

  • Mold or mildew in your bathroom.
  • Condensation on windows during the winter months.
  • Condensation on your pipes.
  • Mold on walls, furniture, floors, or ceiling. (Usually black spots.)
  • Peeling, blistering, or cracking paint.
  • High populations of bugs, spiders, and dust mites.

There are other signs for high humidity, but this little list is a good start.

Now, I”m sure you’re wondering what the signs of low humidity are, so I’ll give you all a list too!

Signs of low humidity in your home:

  • Dry cracking skin.
  • Constantly feeling congested.
  • Constant bloody noses.
  • Irritated skin, eyes, throat, and more.
  • Itchy skin.
  • Constant dehydration.
  • Dry cough.
  • Chapped lips.

As you can see from this list, low humidity is usually a lot easier to detect based on how your body reacts than higher humidity.

If you’d like to read up more on this, or if you’d like to see my recommendations for humidifiers and dehumidifiers, check out this article: How Do I Know if I Need a Dehumidifier or a Humidifier? | What’s the Right Humidity for My Home?

Alright, so we’ve gone over some of the obvious signs of humidity levels, but what’s this test that I promised? Where is it?

Don’t worry, that’s the next section!

The Ice Water Test for Home Humidity:

This is a very simple, very easy test that you can do in your home at any point in time. It’s probably best to run it a few times, once during each season. That’s because humidity levels vary from season to season!

Personally, I prefer using an actual humidity sensor, which costs all of about five dollars, but this is still a neat test–plus you get to drink it when you’re done! (And if you’d like to check out the humidity sensor, I talk more about it at the end of this article.)

How to Run the Ice Water Test

Quick tip: don’t run this test in your bathroom or kitchen immediately after someone showers or cooks. That will skew the test results. Wait a half-hour or so first.

  1. Get a cup–glass ones work the best.
  2. Put some ice in it. Add enough water to mostly cover the ice (like in the picture).
  3. Stir the ice and water to get everything nice and cold.
  4. Set the cup of ice water out and let it sit for three to five minutes.
  5. Check for condensation.

What Do the Ice Water Test Results Mean?

If there is a lot of condensation, then your home’s humidity is probably a bit too high.

If there isn’t any condensation, your home’s air is probably too dry.

If there is just a little bit of condensation (enough to make the glass slick, but not so much that it’s obviously wet), then you’re probably good.

Now, high humidity can be easily fixed with a dehumidifier most of the time. Conversely, a humidifier can address overly dry air. Again, check out this article, “How Do I Know if I Need a Dehumidifier or a Humidifier? | What’s the Right Humidity for My Home?” to see which is best for you and see my recommendations.

Or, if you’d like to run a more accurate test of your home’s humidity, here’s an article I just wrote on doing just that. In it, I also mention the ice water test you see here, but I talk about how you can use a hydrometer and other important stuff there too. Here’s a link to that article: How to (Accurately) Test Your Home’s Humidity.

How Often Should I Test My Home’s Humidity?

Both high and low humidity come with their own sets of risks, which means that you need to be on guard against them.

But that leads to the question, how often should you be checking them?

Honestly, it would be best if you could check your home’s humidity at least once a day, since humidity levels shift between the high and low temperatures of the day. Since it wouldn’t make a ton of sense to run this test with a glass of ice water every day multiple times (unless if you’re a heavy water drinker who likes ice), a hydrometer (or humidity sensor) could be a great choice.

Humidity sensors are easy to come by, and some are pretty stinking neat.

Oh, and while we’re here, let me add that basements are known to have high humidity problems, so that’s definitely worth testing. Even if you have a crawl space, it’s worth looking into. Here’s an article I wrote on that: Does My Basement Need a Dehumidifier?

Now, back to the original question about how often you should be checking these things.

So, since the levels of humidity shift so much, there will be times that you might think you need a humidifier and then a dehumidifier. That might even happen in the same day! Since that’s the case, I personally recommend giving it a few days before you make a decision–unless if your humidity is REALLY high or REALLY low. I’m talking like 25% (on the low end) or 60% on the high end. If it’s just barely outside of the EPA recommended range of 30 to 50 percent you’re probably going to be just fine.

With all of that said, I’m going to repeat something I’ve said many times before: you should probably buy a humidifier AND a dehumidifier regardless of the results.

Woah, what?

First off, I said buy them, I didn’t say run them at the same time!

Let me explain.

So, since humidity levels change so much, you might actually need one machine for part of the year, then you won’t need either, and then you’ll need the other.

For my family, we use the humidifier during the winter, when the air is extra dry. (We also use it when we have head colds and are all sorts of congested. Humidifiers are a huge saving grace there.)

Then my family uses a dehumidifier when it’s the rainy season to discourage mold growth and keep the bugs at bay. Believe it or not, we actually have noticed a drop in the number of six and eight-legged invaders since we started doing this!

But there are also times that we don’t use either.

Odds are that most of you will be in a similar boat.

So, with all that said and done, I’m going to end this post here. Thank you all for reading, and I’ve linked a few articles that I think are relevant, in addition to the three that I’ve already mentioned in this article.

How to (Accurately) Test Your Home’s Humidity

How Do I Know if I Need a Dehumidifier or a Humidifier? | What’s the Right Humidity for My Home?

Does My Basement Need a Dehumidifier?

And now the other related articles…

What is a Water Based Air Purifier? | The Pros & Cons of Water Air Revitalizers

What Are Air Purifiers with Dehumidifiers?

What Are Air Purifiers with Humidifiers

Jonathon Silva

Jonathan Silva is our longtime Air Purifier Essentials author. He has been writing on air purification technologies for his entire professional career.

Recent Posts