Author:
Revised:
August 4th, 2021
Everyone has walked into a basement at some time or another and smelled that unmistakable damp, musty odor. The primary cause of it is excessive humidity, which is prevalent in the summer when it’s humid outside. (For those of you living in the desert, you get dry air but extreme temperatures.)
A common misconception is people think that humid air is heavier than non-humid air. It is actually lighter. Humidity rises, just as steam rises out of a pot of boiling water. If you can’t control humidity in the basement, humidity transfers into the wood subfloor, goes up through the carpet, and continues upward through the first floor.
If your basement is humid, so is the uppermost room in your house.
In the winter, the opposite happens: Your home dries out with the drop of temperature. Cold air doesn’t hold moisture the way warm air does. Your skin dries out, your wooden furniture starts to crack, and breathing issues can make your life unpleasant.
You can’t do anything about the weather, but you can take steps toward making your living space more comfortable. You can combat humid and dry air and gain comfort. This article will discuss your options.
Here at Fire & Ice, our maintenance and sales folks have helped thousands of customers with hot or cold spots, with dry and humid air. We have plenty of suggestions to make your home more comfortable.
Summer Humidity
It’s hot and humid outside, and when you leave that door open, humidity comes in. That’s unavoidable. Unless you want to live like a hermit, the doors to the outside world open and shut. Fido wants to be outside, then inside.
For the most part, humidity starts in your basement. Many people think that their concrete floors and cinder block walls are all sealed. They’re often not; water and moisture are seeping in. Concrete is porous.
And sometimes an air conditioning unit is over- or undersized. If a unit is oversized, it cools the house down too quickly, and then it shuts off, which doesn’t give it enough time to dehumidify that air. If a unit is undersized, it’s going to be fighting uphill all the way. It’s no match for a hot, humid house.
If Your House Is Too Humid in the Summer
You’ve got that cool, dark, damp place where you also see insects and spiders. Dust mites love wet spaces. If you have a lot of spiders in your basement, they’re there because you have insects down there. And you have insects down there because it’s humid. If you want to get rid of them, you need to dehumidify your basement. They can’t survive in a dry environment.
One of the questions we ask during our comfort survey with a homeowner is, “Does the home get muggy in the summer?”
A home getting muggy in the summer can mean a couple of things. First, we need to focus on dehumidification.
In a super humid environment, you can get peeling paint. You may notice problems with wooden instruments such as pianos and guitars. It can also cause problems for wood floors. Wood expands with moisture.
Anything past about 60% relative humidity, and you’ll be at risk of developing black mold.
Problems Caused by High Humidity:
- Dust mites love wet spaces. Where they multiply, you can bet that spiders and other insects that feed on them will as well.
- Mold and mildew start in humid climates. This is an issue in many basements, and that dampness can creep upward to other levels of your home if you’re not careful. Your ductwork is also a common home for them.
- Asthma and allergies. If there are mold spores in your air, you won’t breathe as easily.
- Hot upper floors. Is your master bedroom too hot? Is the room in the attic unlivable? It’s not just a temperature issue. It’s also a humidity issue since the most humid air will rise to the top of your home.
- Wet woodwork. Wooden floors and furniture can absorb water, making them expand. Too much expansion can lead to warping.
How to Remove Humid Air
There are multiple ways to attack humid air in the basement. One is a war of attrition, which is a two-speed or variable-speed AC. We can’t stop the humidity from coming into the house, but we can fight it.
That’s when a two-speed or variable-speed air conditioner is nice. When an air conditioner runs, it’s removing humidity from the air as well. Air conditioning is more about removing hot air than providing cool air.
Because a two-stage AC runs for longer than a single-stage (albeit at a lower power level), it’s removing more humidity from your home. Similarly, a variable-speed system will remove even more humidity. It will run at a low speed for a slightly longer run cycle, which allows more time for the air conditioning to remove that humid air and create a more comfortable environment.
Or we can attack humidity at its source. We can kill it in the basement and get the relative humidity down. That solution would call for a room dehumidifier (or even a ductless mini-split). These will remove humidity from the basement only.
If your entire home is still suffering from the effects of damp air, another option is a whole-house dehumidifier. Certain models can remove up to 100 pounds of water per day.
For the handymen out there, you can install vents or exhaust fans - especially in areas that create moisture, such as the kitchen, bathroom, laundry room, and basement. You may also want to install fans in your attic.
The cheapest option that requires the least amount of hassle is to buy a room dehumidifier. We’ve seen plenty of homes make good use of them. They do require maintenance - emptying the tank as needed - but they are a good one-room solution.
For homeowners handy with tools, here are a few more suggestions:
- Insulation protects against cool and warm. Install insulation around water pipes to help decrease ‘sweating.’ Add waterproof insulation on toilet tanks.
- Install weather-stripping on your windows, caulk the frames, and ensure that the glazing is in good shape.
- Waterproof your home, including the basement. Make that concrete airtight.
- Clean and repair any problems with your roof, gutters, and downspouts. These are major sources of water damage. Loose shingles can cause water to infiltrate your attic, soffits, or walls.
One nice side benefit to removing moisture: Keeping humidity down. You don’t have to cool your home as much, saving you cooling costs in the summer. You’ll feel cooler in drier air.
Ductless Mini-Splits and Humidity Removal
When they are in their cooling cycle, ductless mini-splits do remove humidity. Residential mini-splits generally go up to five heads. The more heads you have in a system, the more complicated it becomes to install, service, and maintain the system. The cost increases with each head. They allow you to remove excess heat/cold in multiple rooms at once.
The biggest factor that affects the cost of a mini-split is the number of “heads” that it has. A head is an individual indoor unit that is connected to the outdoor unit and provides cooling or heating to a room or area.
Many homeowners won’t need these extra indoor units if they have the ductwork installed for a traditional HVAC system. However, there are homes without proper ductwork, and these homes don’t have convenient areas in which ductwork could be installed. In these situations, their only option might be a ductless system.
Mini-splits can work wonders, but they can condition the air in limited spaces. Unless your house is small, they are not a great whole-house option.
If Your House Is Too Dry in the Winter
Telltale signs for a home that’s too dry usually boils down to the comfort of the person. If it feels dry, it probably is. And you don’t need a humidistat to remind you.
Cold weather sucks the humidity out of the air.
Breathing dry air can cause respiratory ailments such as asthma, bronchitis, and sinusitis. It causes nosebleeds, especially in children. It can cause dehydration since body fluids are depleted during respiration. Other health issues common to dry air include sore throats, eczema, and itchy skin.
Typically it’s drier outside in the winter, and when the furnace is going, it dries out the air even more. When it’s too dry wood dries out and shrinks, and you get gaps in the floorboards.
The relative humidity in central Ohio can reach as low as 15% in the winter. For reference, the average relative humidity of the Sahara Desert is 25%.
Variables affecting indoor humidity levels include: Is the house tight, does it have new windows, is it a newer build, is it sealed, or is it a house built in the 1900s, or is it a farmhouse that leaks hot and cold air?
Problems Caused by Low Humidity:
- Dry wood. Cracking floorboards and wooden infrastructure of your home. When wood dries out, it shrinks.
- 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.
- Skin and throat issues. Dry, cracked skin and a sore throat are hallmarks of the colder winter months.
- Cold spots in the home. This could be caused by an under- or over-sized furnace system, your ductwork, or drafty windows. But often, it’s related to humidity.
How to Add Humidity to the Air
One solution is a whole-house humidifier.
A lot of literature says you shouldn’t have a humidifier because it puts moisture in the ductwork. Is that true? Yes, to a certain degree. But the ductwork also has hot air blowing through it during the winter, and bacteria tend not to grow when it’s hot.
One of the things I tell people with humidity problems: having humidifiers is a strange concept because it helps to maintain rather than increase. Putting a humidifier on your system isn’t going to make your house at 50% humidity in the winter. But it’s better than not having one.
There are different levels of humidifiers:
- Bypass: Conditions air up to around 2500 square feet.
- Power humidifier: About 3000 square feet.
- Steam humidifier: 3000 square feet and up.
Next Steps
Our sales staff always begins the conversation with homeowners with an eye on home comfort, first and foremost. Yes, we sell HVAC equipment, but we hope to provide solutions to problems.
While an ideal relative humidity level can vary from person to person, 30-60% is the comfort zone. When the numbers drop below 30 or rise above 60 is when comfort dips.
The big question is how much discomfort are you and your family willing to put up with before you take action. We’ve talked to hundreds of homeowners who have mentioned humid and dry spots, but have simply learned to live with them.
What we want to provide as HVAC experts is to point out options along with a variety of prices.
If you think you could benefit from a dehumidifier, a humidifier, or ductless mini-splits, we’d love to talk to you. Check out the map below to begin the process of receiving a free estimate for installation.
