How To Fix It

Signs of High Humidity in Your Home

It’s normal to have at least some humidity in your home, and in fact, having a certain level of humidity indoors is good for you. Prolonged contact with desiccated air will cause your skin to dry out and be cracked and painful, and dry air is better at generating static electricity, which is annoying when you get a shock every time you touch a metal object.

But while not having enough humidity in your home is bad, having too much humidity is arguably worse. The signs of high humidity in your home include condensation on your windows and mirrors, the discoloration of wood surfaces, and the smell of mildew, among other things.

In this article, we’ll be covering what the symptoms of high humidity in your house are, as well as how high humidity can affect your home and what you can do to get your humidity levels back down to lower levels.

Related: Why is Humidity Higher Inside Than Outside?

How Much Humidity Is Too Much?

The ideal level of humidity for comfort and health is generally considered to be between 30-50%. This percentage is the relative humidity, which differs from the absolute humidity; let’s quickly explain how these two types of humidity differ.

To understand the difference between absolute and relative humidity, you first have to be aware of the fact that the temperature of the air affects how much water vapor it can hold. Cold air can hold less vapor, while hot air can hold more.

  • Absolute humidity is a measure of the actual amount of water vapor in a cubic meter of air.
  • Relative humidity is a measure of how much vapor is in the air compared to how much could be in the air based on its temperature.

This means that for the same amount of water in a cubic meter of air, the relative humidity will be higher if that air is cold, and lower if that air is warm.

Signs of High Humidity in Your Home

The easiest way to determine whether the humidity in your home is within acceptable limits is to use a hygrometer. A hygrometer is a device that measures the level of humidity in the air. Most hygrometers are designed to measure relative humidity, which is a more useful figure to know.

Both digital and analog hygrometers are available, and it’s pretty easy to find either type of hygrometer for a decent price. However, if you don’t have a hygrometer and don’t feel inclined to get one, there are still a few ways you can tell if the humidity in your home is too high.

Here’s what you should be on the lookout for if you think your house might be too humid:

Condensation on Your Windows

If there is too much moisture inside your home, eventually it’ll start to condense on various surfaces. This usually occurs on surfaces that have the largest contrast in temperature to the surrounding air, which are usually windows, pipes, or mirrors.

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If you notice what looks like a fog clinging to your windows and they feel damp to the touch, there’s probably way too much humidity in the room. Not only does this make it way harder to actually see out of your windows, but too much humidity can actually damage your windows and other objects in your home, as we’ll explain later.

Smell of Mildew

It’s normal to have a bit of mildew in your home, particularly in places that don’t get much airflow, such as basements and crawlspaces. You can usually smell this mildew even if you can’t see it; it typically has a damp, musty smell, similar to wet socks or rotting wood.

It’s more serious if you start noticing the smell of mildew in parts of your house where you didn’t smell it before. Even if you can’t see it, if you can smell it, that means mildew is there, and if mildew is there, it means that there’s too much moisture around.

Visible Mold

It’s one thing to smell mold, but if you actually start seeing it around your house, that’s a sure sign that humidity levels are way too high. Mold commonly grows in rooms of your house that are frequently warm and damp, like your kitchen and bathroom, but if you start seeing it in other parts of the house then that’s a real cause for concern.

Related: How to Prevent Mold in Window Air Conditioner?

Aside from just looking gross, mold can cause a variety of health issues if left untreated. When dealing with mold, it’s not enough to simply lower the humidity of the room the mold is in; you have to deal with the problem at its source and actually take care to clean up any mold colonies you find.

Spotting and Discoloration of Wood Surfaces

Prolonged exposure to any kind of moisture is bad for anything made out of wood. This includes furniture, floors, and fixtures like doorways and window frames. Wood is a hygroscopic material, meaning it likes to absorb whatever moisture it comes into contact with.

Wood that has absorbed too much water will start to deteriorate, which manifests itself as discoloration on any affected wood surfaces. If this goes on for long enough, the wood will rot completely.

Worsened Allergies

If you find that you tend to suffer more from allergy symptoms such as coughing or wheezing more often when inside your home, it could be the result of an excess of mildew caused by the high humidity. If you have a condition like asthma, even the high humidity itself might make it more difficult for you to breathe.

Why Are High Humidity Levels Bad?

You should probably have an idea of why excessive humidity is such a problem based on what the signs of it are, but let’s take the time to fully elaborate on this a little further.

High humidity is bad for your home itself because it’ll cause any wooden materials in your home to become warped and eventually rotten. We’ve already mentioned that wood absorbs water, and when it does, the wood swells up and changes shape. Wood doesn’t swell up evenly when exposed to moisture, which makes the warping even worse.

If the wood in your home really starts to rot, it can result in some costly repairs. If the problem gets bad enough, you may be forced to replace your floors, window frames, and other affected fixtures.

Prolonged levels of high humidity are also worse for your health. Aside from promoting the growth of mold in your home, humid conditions are excellent for the spread of dust mites. Both mold and dust mites are known to cause allergy symptoms, so if you’re susceptible to either of those things then you’re really going to suffer in a house that is too humid.

Lastly, living somewhere where the humidity is too high is just plain uncomfortable. Think about any time you had to sleep in a room that was just a little too humid, and you’ll know exactly what we’re talking about. Spending too much time in an area that is too humid will significantly decrease your quality of life.

How Can I Reduce the Humidity in My Home?

There are plenty of ways you can reduce the humidity in your home if you need to. Here’s what you can do:

Use a Dehumidifier

A dehumidifier does exactly what you’d expect based on the name; it removes the humidity from an enclosed area. Dehumidifiers work by drawing in warm, moist air, separating the moisture from the air through condensation, and then sending the cooler, dry air back into the room.

There are a couple of types of dehumidifiers to consider; you have portable dehumidifiers that can remove the humidity from a single room, and whole-house dehumidifiers that can remove the humidity from your entire home. Most whole-house dehumidifiers connect directly to your HVAC system and can’t be moved once they’re installed.

Run Your A/C

If you have an air conditioner, running it will also help to remove some of the humidity from your home. This is because air conditioners also remove some of the moisture from the air through condensation, which helps lower the temperature of the air it puts out.

Related: Which Is Better An Air Purifier Or An Air Scrubber?

Air conditioners are not nearly as effective as dehumidifiers when it comes to reducing humidity, however, so don’t assume you can use an air conditioner and a dehumidifier interchangeably.

Ensure Your Home Is Properly Ventilated and Insulated

It’s important to make sure that your home is both adequately ventilated and insulated, as both of these can help keep the humidity levels in your house at reasonable, stable levels.

In areas of your house that frequently get hot and moist, having enough ventilation can help remove excess humidity from these areas when it builds up. This is why so many bathrooms have ventilation fans.

Making sure your whole house is insulated properly keeps it weatherproof and helps to maintain a consistent and comfortable indoor climate in all seasons. If you haven’t already, you should make sure that the doors and windows in your home are sealed up properly, and that your home’s ceiling and walls have a sufficient amount of insulation.