Have you ever noticed how a hot and humid summer day feels worse than a dry one? Or how dry winter air feels more bitingly cold? Just as you’re thinking about the way those harsh sensations, it’s just as taxing on something else: your energy bill. But what does your home’s humidity have to do with your energy costs?
Just like the actual temperature, the relative humidity in your home affects your home’s cooling and heating. Depending on the temperature and humidity, it can force your cooling or heating systems to work harder than normal. By understanding the role that humidity plays in the home environment, you can give your energy costs a helping hand while feeling more comfortable in your living spaces.

What is Relative Humidity?
Relative humidity is the amount of water that’s in the air in comparison to how much water the air can actually hold at a certain temperature. For example, if your home’s relative humidity is at 40%, it would mean that the air in your home contains 40% of the moisture that it can actually hold at its current temperature.
To keep an eye on the temperature and relative humidity of your home, it’s recommended to get a hygrometer. By monitoring the relative humidity of your home, you can take measures to adjust the humidity so that your home’s heating or cooling systems can work at optimal efficiency. This is especially important for homeowners that live in areas with changing seasons.
What Affects My Home’s Humidity?
There are multiple factors at play that can affect the overall moisture in your home’s air. A lot of it has to do with moisture already being carried by the air. This is especially so for areas where the climate can be humid. According to the US Department of Energy, “air movement accounts for more than 98% of all water vapor movement in building cavities—generally through any available hole or crack in the building envelope.”
Whether it’s a space between a door and its frame, or a crack in your basement wall, moisture vapor will be able to seep through and change the humidity of your home. There is also moisture diffusion through building materials and heat transfer to consider. Be sure to address any water leaks in your home as well.
How Does My Home’s Humidity Impact My Energy Costs?
Whether the climate is hot or cold, the relative humidity in your home can have an effect on how it feels in the house. This is even when you’re cooling system or heating system is running. In the summer, when it can get hot, you’ll want to keep the humidity from getting too high. In a humid environment, it can be harder to cool off, which can cause your air conditioning to run for longer and even then, it won’t achieve as effective of a cooling effect as it would if the air were drier.
Inversely, for a colder climate, having some humidity in the air of your home can help you retain some of the warmth from your heating system whereas dry air would make your heating system have to work harder to maintain a warm indoor climate. Straining your cooling or heating will only increase your energy costs.
By controlling the humidity levels in your home, you can maximize the effectiveness of your cooling or heating. While you will be feeling more comfortable, your energy bills will also be looking better.
Proper humidity control and its energy cost benefits will also be crucial in the near future. According to a study done by Nature Communications, “Ignoring the role of humidity leads to underestimating the climate sensitivity of demand, challenging the resilient operation of power systems—especially under future warming scenarios where summertime energy production will be further constrained.” Learning how to manage your indoor humidity can have long-term benefits. It can help alleviate potential strain on community power supplies as the world continues to warm up.
Other Consequences of Poor Humidity Control
The EPA recommends that you maintain an indoor humidity between 30 percent and 50 percent. Anything above 60 percent brings in the risk of mold growth. High humidity can also attract unwanted pests like dust mites. Both mold and pests can lead to additional costs in their removal but can be avoided with proper humidity control. While the costs can differ depending on your contractor, the severity of your situation, and location, mold removal costs average at around $2,300 for a typical home and pest control services can average at around $250 for a typical home.
If the growth of molds and fungi are not addressed, it can also lead to wood rot in your home’s wooden structures, which in turn can lead to other repair costs. For example, the cost of replacing rotten floorboards can range from hundreds to thousands depending on the size of your room. Floor joist repair can reach as high as $10,000 for just a small room.
How Can I Control My Home’s Humidity?

The best way to control your indoor humidity is to take measures to prevent moisture from intruding into your home. For your foundation and lower level, there are some waterproofing measures that you can take. Along with waterproofing your basement or encapsulating your crawlspace, you will need to also seal any gaps in your home that may allow outside air to invade. These can include anything from gaps around your pipes that go to the outside to windows that are becoming loose. Some of these gaps, like around windows, can be fixed with caulking.
Last but certainly not least, you will want to consider getting a dehumidifier and/or a humidifier to further adjust the indoor humidity to your desired specifications.
Here are some other ways that you can help ensure that moisture doesn’t intrude into your home:
- Ensure that the ground is sloping away from your foundation to prevent rainwater from simply sitting against your foundation. This will help relieve hydrostatic pressure and reduce the chances of foundation cracks or water pushing its way through any spaces leading into your basement or crawlspace.
- Clean your rain gutters and make sure that your downspout is sufficiently long enough. This ensures that rainwater is dispensed far from your foundation.
- Check for any leaks in your home. Whether it’s from your plumbing or your laundry appliance, a leak means unwanted moisture invading your home space. Be sure to fix these leaks promptly.
- If you notice condensation on a surface, like that of an appliance or a window, it means the object’s surface is too cold and needs to be warmed. This can be done by using fans, opening room doors, and even moving furniture away from corners. Doing these will promote better air circulation for warmer air to reach those cold spots.
Creating a Safe and Dry Future In Your Home
By using these various methods to bring your indoor humidity under control, you can prevent problems associated with excess humidity. The additional benefit is protecting your wallet against high energy bills, water damage, and home repairs. Some of these methods will involve an investment, such as waterproofing. But these measures will pay off in the protection they provide to your home and everything within. With the global climate warming up, many regions will be experiencing greater levels of heat and humidity. This can create a higher energy demand on the communities affected. Controlling your indoor humidity may seem like a small thing, but it can help prevent some of the costly repairs that you would otherwise experience.
Give us a call at (866) 485-6695 and we’ll have a crawlspace specialist provide you with a free inspection and a zero-obligation price estimate!
Sources for Links:
What are the Main Ways to Control Moisture in Your Home?
https://www.epa.gov/mold/what-are-main-ways-control-moisture-your-home
The Critical Role of Humidity in Modeling Summer Electricity Demand Across the United States
https://www.nature.com/articles/s41467-020-15393-8#Abs1
Energy Saver: Moisture Control