What's Causing High Humidity in Your Home?
Does your home feel like a sauna in the summer? Elevated humidity levels affect numerous homes across the U.S., especially during the summer. Humid air can lead to poor air quality, health issues, mold growth, and damage to your home.
It's worth trying to learn why your house has excess humidity and how you can fix the problem. You can make investments in your HVAC or AC system to reduce high humidity. Here's a quick guide to the solutions:
Understanding the Causes of High Humidity in a House
There are many external reasons why your home is too humid. An obvious one is the climate—hot, muggy weather can lead to excess moisture and a stuffy house with sticky air. Humidity can also originate from the soil, especially if your home is close to a lake or river. Surplus moisture from cooking, bathrooms, appliances, and showers can increase the moisture levels in your house.
However, you can't exactly pick your house and move or stop using water. Your house's HVAC system and insulation should be able to remove enough excess moisture and keep out air to avoid discomfort.
Two Key Reasons Why Your Home Feels Humid
Most of the time, your house feels humid because of two reasons:
1. Your HVAC system isn't effectively reducing your home's humidity.
2. Your house isn't preventing humid outdoor air from entering.
If you solve these two problems, you will be well on your way to a more comfortable house.
Is Your HVAC System Reducing Humidity?
Having an HVAC system that can't dehumidify your house is a major contributor to humidity. If your home feels like a rainforest, you should evaluate whether your HVAC system is working properly.
How Air Conditioning Systems Affect Humidity
If your air conditioner is outdated or aging, it's probably struggling to keep your home cool and refreshing. There are numerous ways an AC system can fail. In all these situations, inadequate HVAC results in poor ventilation, leading to a damp, stuffy, and unpleasant home.
- Old AC system - If your AC is old and breaking down, it will stop effectively removing humidity. AC systems typically last about 15-20 years before starting to show signs of age.
- Poorly maintained AC units - After prolonged usage or debris build-up, AC units may develop mechanical issues with evaporator coils or fans. These issues can cause humidity as they cause your AC unit to function inefficiently. If this occurs, contact an HVAC technician to perform maintenance on your unit.
- Incorrectly-sized AC units - Your AC may be too small or too large for the house. This causes humidity to hang around instead of being removed.
- An AC system that is too small won't have efficient output and operate longer than it should. In addition to not efficiently cooling your house and wasting energy, a system that is too small won't remove enough humidity from the air.
- Alternatively, you can have a system that is too large and is cooling the air before adequately dehumidifying. If you hear short cycling, when your AC equipment repeatedly turns on and off in brief intervals, this typically signifies that your AC equipment is too large for your space, cooling the air so rapidly that it doesn't have enough time to thoroughly dehumidify the air in your home.
The single most crucial action you can take to decrease humidity in your home is to upgrade your HVAC and air conditioning system to one specifically designed for your home that can tackle the challenge of high-humidity air.
How Sealing And Insulating Your Home Affects Humidity Levels
A house's most important function is preventing external weather from entering the home; otherwise, you're living in a glorified tent. If your house doesn't have a strong building envelope—sometimes referred to as a thermal barrier or thermal envelope—you will have issues with humidity. The building envelope is the boundary that separates the interior of your house from the outdoors.
If there are holes in this boundary—or if it was never correctly constructed—humid air can enter your home, making it extremely uncomfortable. Regrettably, your home's thermal boundary likely contains numerous holes and leaks.
How Can You Tell If Your Building Envelope Is Contributing to Your Humidity Problem?
Most houses in the U.S. have numerous air leaks. If you haven't had your house sealed, there's a high chance that the open gaps and seams in your house are significantly contributing to your humidity issue (especially if your house is older).
As a start, you can conduct a do-it-yourself air leak sweep in your home. This involves walking around your house and examining where potential leaks may be (windows, chimneys, outlets, attic hatches, doorframes, etc.). For a more comprehensive assessment, you can hire a qualified technician who can perform a blower door test to find leaks.
How To Permanently Reduce Humidity In Your Home
Now that you know why you're experiencing humidity, it's time to solve it once and for all.
We understand that many homeowners try to address the issue by purchasing small, standalone dehumidifiers. While a standalone dehumidifier can work in a damp basement or for other limited uses, it won't permanently solve the problem. Cleaning standalone dehumidifiers is a chore—smaller dehumidifiers are unsightly and typically need to be emptied daily.
It can also be nearly impossible to remove mold and mildew from a unit that's been operating for some time. Using smaller dehumidifiers will only increase your electricity bill without resolving the core problem of poor ventilation—a problem that will need addressing sooner or later, with or without dehumidifiers.
The two best ways to permanently reduce humidity are obtaining a quality HVAC system that can meet your needs and making sure your home is properly insulated.
Upgrading Your HVAC to Handle Humidity
Replacing your air conditioning system might sound intimidating, but it's the best path forward for dehumidifying your house. A well-designed HVAC system will actually solve the problem.
In the long term, addressing the real problem is a far better value for your money, time, and mental resources. Upgrading to the correct HVAC is much more energy-efficient than running several smaller appliances alongside your current HVAC. If you try to piece together a solution without resolving the actual ventilation issue, you'll end up in a spiral of never-ending purchases and annoyances.
The next question, inevitably, is what kind of HVAC or air conditioning system will be the most effective at making your house feel cool and clean? We've examined the research, and there's a clear winner. The top HVAC system for high humidity is an air-source heat pump.
How Do Heat Pumps Help With Humidity?
If you're unfamiliar with heat pumps, here's the lowdown: heat pumps are a more advanced and intelligent way to cool, dehumidify, and warm your home. Ironically, heat pumps don't actually generate heat. Instead, heat pumps operate by transferring heat energy from the outside air depending on whether you are cooling or heating your home. During the winter, they move heat from the outside air to the inside of your home. In the summer, they reverse the process, transferring heat from inside your home to the outside.
Critically, a heat pump not only cools your home during the summer but also extracts moisture from the air, making it an excellent solution for homes in humid climates. Because of their efficiency, they can significantly reduce your energy waste and reduce your carbon footprint. Heat pump installations are now eligible for significant federal tax credits that make them a more affordable option.
Heat pumps can be installed almost anywhere since some models don't require ductwork (though heat pumps can also utilize existing ductwork). They're also extremely quiet and odor-free—heat pumps even help purify the air while operating. Moreover, they heat and cool uniformly—so every area of your home feels exactly as you want it to.
In summary: You'll prefer your heat pump over your old air conditioning system. After all, 81% of individuals say their home comfort improves after installing renewable-based heating systems like heat pumps, according to the European Environmental Bureau.
Improving Insulation In Your Home
While a better HVAC system is the most crucial factor in reducing humidity, it's essential to ensure that the air you condition remains inside your home to maximize benefits. You will need to professionally air-seal your home and close up the gaps in your thermal envelope to fully address excess humidity.
When you have your home air sealed, you'll fill in all the cracks and gaps in your thermal envelope that allow air exchange with the outside. This will keep hot, humid air outside and cool, filtered, conditioned air inside—where it should be.
However, if your home's insulation is outdated or inadequate, or if there are significant areas of your house that were never insulated in the first place (such as a garage), your home's ability to retain cool, dry air will be significantly compromised.
In short, adding or upgrading insulation may be an effective method for reducing humidity in your home. Before investing in insulation, it's worth consulting with an expert. For example, you should be aware of the main types of insulation—fiberglass, spray foam, and cellulose, which each have pros and cons. QuitCarbon can connect you with an expert that will make the right recommendations for your home.
Neither of these steps is a good DIY project; designing and installing a home climate system that will keep a house comfortable long-term requires expertise and years of hands-on training. With QuitCarbon, it's easy to get expert help from people who have been doing this for a long time. We have helped hundreds of homeowners install heat pumps and insulate their homes. Homeowners can get a free "Electrification Program" from QuitCarbon which will give you recommendations from a specialist and refer you to our network of trusted contractors.
