What’s the Best Humidity Level For Your Home, and How Do You Control It?

I have huge humidity issues. While this isn’t uncommon in Central Ohio, most people are used to having to add moisture in the winter. Often, I find myself having to dehumidify even in the winter.

My problems aren’t the same as yours. But everyone who owns a home needs to be paying attention to their humidity levels. If you’re not, I guarantee it’s hurting you in several ways. Maybe it’s allergies, maybe it’s mold, maybe it’s just a general sense of dry-skinned discomfort in the winter.

You may be aware of the humidity problems you face, but many homeowners have no idea they can have better comfort through better humidity control. That’s what we’re going to talk about in this article. We’ll cover:

1. Why humidity matters and what problems it can create and solve
2. What you can do in every season to be more comfortable
3. What your entire HVAC system (including A/C and furnace units) has to do with moisture control

Ready to feel better in your home? Good. Let’s get started.

Why Humidity Matters in HVAC

Humidity equals comfort. Don’t believe me? Spend 10 minutes in a sauna at a certain temperature, then 10 minutes in a steam room that’s at the same temperature. There’s quite a difference.

Your home isn’t a sauna or steam room, but if your humidity gets out of control, it can sometimes feel like it.

Temperature is what we think of when we consider indoor comfort, but humidity levels matter almost as much. You’ve probably heard the term “dry heat” and how it’s more bearable than the “wet heat” of a humid environment. This is completely true.

In practice, your 72-degree home could easily be uncomfortably hot with humidity that’s too high, just as it can be too cold in the wintertime if you have dry air.

So if you’re paying to heat and cool your home anyway, why not do something about this?

What’s worse is that there are other problems that humidity can cause if it gets too high or too low.

Problems Caused by High Humidity:

1. Dust Mites. These absorb ambient moisture and can proliferate throughout your home. In turn, they draw spiders and other insects that feed on dust mites.
2. Mold and Mildew. This is an issue in many basements, and can also creep upward to other levels of your home if you’re not careful.
3. Health and Allergies. If there are mold spores in your air, you won’t breathe as easily. At its worst, it can affect the health of you and your family.
4. Hot Upper Floors. Is your master bedroom too hot? It’s not just a temperature issue. It’s a humidity issue, since the most humid air will rise to the top of your home.
5. Trouble Sleeping. This could be due to overall temperature or moisture that causes night sweating.

Problems Caused by Low Humidity:

1. Dry Wood. Cracking floorboards and wooden infrastructure of your home.
2. Illnesses. Low humidity is a good environment for many bacteria and viruses to exist. It’s a big part of the reason flu season hits over the winter in most parts of the country.
3. Skin and Throat. Dry, cracked skin and a sore throat are hallmarks of the colder winter months. They don’t need to be.
4. Cold Spots in Home. This could be the power of your furnace system, your ductwork, or drafty windows. But often, it’s related to humidity.

There may be other reasons we’re forgetting, but those are the issues most commonly faced by homeowners that we talk to.

Now let’s start to talk about fixing these issues.

What’s the Best Home Humidity Level?

Most expert sources agree that anything between 30-60% humidity is acceptable for a home environment. Anything lower will create problems, just as anything higher will create problems. Depending on where you live and your humidity concerns, your ideal level may be on the upper or lower end of that range.

That said, there isn’t a central authority of humidity control that decides what the best level is. But air quality experts do agree on a range of acceptable humidity levels.

HVAC.com puts the ideal level at 40%. Aprilaire, a company that specializes in indoor air quality products, cites 50% as the target. Both are right, because those levels exist in an acceptable range for home humidity.

For example, remember that we mentioned dust mites earlier? They can exist in your home at or above about 50% humidity. More of them will be able to thrive at even higher levels above 60%.

Conversely, studies have shown that many viruses stay alive in the air much longer at humidity levels below about 40%. In fact, this is true of the coronavirus that brought the world to its knees in 2020.

RELATED: Can HVAC Protect From Coronavirus and Other Illnesses

So humidity levels really matter!

Managing Humidity in the Summer

Summers here in Central Ohio get very humid. If you’re in the southeastern part of the country, this can be even more true.

Some people think that getting the store-bought dehumidifiers will take care of humidity issues. They might, but only for very mild cases. Most times, the best these devices can hope to accomplish is to reduce humidity levels in a single room.

This might help you sleep at night, for example, but won’t do anything about the allergens, dust mites, and mold issues that you might develop if you ignore the rest of your house.

The solution in these cases is a whole-house dehumidifier. These are able to regulate your entire home’s humidity, and it works in conjunction with your HVAC system.

RELATED: Is a Whole-Home Dehumidifier Right for Me?

The other nice thing is this: by keep humidity down, you don’t have to cool your home as much, saving you cooling costs in the summer.

There’s an upfront cost to a whole-home dehumidifier, and some people struggle to see the benefit. But if humidity is an issue, you’re gambling with your health and comfort, and also risking having to have mold removal down the road. If you’re concerned about any of these, the risk isn’t worth it.

Managing Humidity in the Winter

The flip side of the whole-home dehumidifier is a whole-house humidifier.

While a whole-house dehumidifier can be ducted into your HVAC system or standalone, a whole-home humidifier will always be ducted directly into your system. When the fan in your furnace unit turns on (which also moves air for the air conditioner), it will spread moisture throughout the home to keep it from being dry.

Want to reduce your risk of the flu? Or to stop it from spreading when your kids bring it home from school? Keep your humidity levels up. Want to avoid having to take out a loan just to buy enough skin moisturizer in the winter? Keep your humidity levels up.

The individual units you see at department stores are again ok for individual rooms. They can be useful for sleeping better occasionally, for example. But doing that is ignoring the rest of your home, where you spend a lot of time in your life.

When You Don’t Need These Products

Let’s say you live in Arizona and it’s never too humid. You won’t need a dehumidifier in that case. Or you live on the coast and it’s constantly muggy. You won’t need a humidifier there. Or your home is insulated well, doesn’t have a basement, and never seems to have high-humidity days. You’re good to go already.

But for the majority of us, one or more of these issues will be a problem. Don’t ignore it, or you’re ignoring your own wellbeing.

And how will you know your humidity levels are ok? Keep scrolling. A bit further down we talk about tracking humidity, so that you can be certain you’re optimizing your home’s comfort.

How Your Air Conditioner Controls Humidity

Wait, what does air conditioning have to do with humidity control? A lot, it turns out.

One of the functions of your air conditioner is to absorb humidity from inside your home and expel it outside. Some A/C units are very efficient at doing this.

This is part of the reason why not all air conditioners are created equal. In particular, variable-speed air conditioners are great at this, compared to single-stage and two-stage ACs. This is because they can dehumidify while operating on lower power settings. I’ll give you an example:

Let’s say you want your home to be 72 degrees, and 45% humidity. The air conditioning might get the temperature to 72 degrees, but the humidity is still at 53%. So you want to remove more moisture, but without making it any colder. What’s the solution here?

For a single-stage air conditioner, the answer might be “there isn’t a solution.” Or at least, there isn’t one without the aid of a whole-home dehumidifier. Since the air conditioner can only turn on or off 100%, to remove more moisture would be to also make it colder.

But a variable-speed system can operate as low as 40% capacity, which will give you a more moderate stream of cold air. However, it will continue to remove moisture through this operation.

So a more advanced system may actually run longer, but it’s using less energy since it’s operating at a lower power, and it’s making your home more comfortable in the process.

ALSO READ: One-Stage, Two-Stage & Variable-Speed ACs: Differences & Benefits

This won’t always be the right solution. Other times, no A/C will be enough for a very humid home, and you’ll want to supplement it with a whole-house dehumidifier. But the range of options available to you with air conditioning units means you have different ways to tackle the same problem.

Tracking Humidity

So how will you know your humidity is within acceptable ranges? After all, many homes have no way of tracking this. Let’s look at some of your options.

Thermostat

Many modern thermostats have displays for humidity level, and can actively help you manage this level in your home. Some can run your blower fan even when the air conditioner isn’t running in order to remove more moisture from the air.

Humidistat

A humidistat is a device specifically designed to monitor humidity levels in a space. Most modern humidistats are digital.

Your Humidifier or Dehumidifier

Whole-home dehumidifiers and humidifiers will have built-in sensors that do this. However, there can be a problem with this method. If your dehumidifier is in your basement, for example (which is usually the best place for it), or your humidifier is with the furnace in a utility closet, it’s taking the humidity level in that room. You’d rather optimize it for the living space on the main floor of the home where the most people are.

So the takeaway with that last one is to talk to your HVAC partner to make sure these devices are properly connected to your thermostat, and that you have a thermostat that’s capable of detecting humidity levels. Otherwise, you’ll be optimizing humidity levels for areas of the home where no one ever visits.

Control Your Comfort

When we visit homeowners, they’re usually not thinking about humidity. They’re thinking about heating and cooling.

This is why we sit down with every potential customer and walk through what we call “comfort concerns.” A lot of times, you’ll be experiencing one or more of the problems we’ve discussed in this article. But it’s rare to find someone who realizes that these problems can be solved with HVAC solutions.

If your HVAC partner isn’t listening to your problems in this manner, they’re not really looking out for you. I don’t care if you’re in our service area or not; you should be working with someone who is trying to be proactive about managing your home’s comfort. Not just someone who wants to sell you a system as quickly as possible.

Because HVAC isn’t just about the bottom line. It’s about creating a home environment where you can enjoy your life.

That’s what we’re here for at Fire & Ice. If you’re in Central Ohio, plug your zip code into the box below to get started. We’ll be happy to listen to your concerns and help you find the best solutions for them.