Do Dehumidifiers Get Rid Of Bugs – Insects And Humidity

Heat and humidity provide a favorable breeding environment for pests. Given that dehumidifiers can reduce relative humidity, we often wonder if they can help counter bugs’ invasion in our homes.  

Dehumidifiers reduce humidity levels to 30-50%, which can deter bugs and insects that prefer high relative humidity conditions, such as roaches, ants and spiders. Relative humidity levels above 70% provides a favorable environment for the survival, reproduction and growth of pests. Dehumidifiers reduce humidity and prevent these favorable conditions.

If you live in a humid area dehumidifiers can help solve your pest problem. This article discusses the relationship between humidity and different types of insects and how dehumidifiers can eliminate them.

Do Dehumidifiers Prevent Bugs? 

Dehumidifiers maintain an ideal humidity level, i.e., between 30 to 50%. Since most moisture-loving pests prefer 70% or more relative humidity, dehumidifiers certainly do deter them.  

However, a dehumidification system doesn’t entirely prevent insects as several factors apart from humidity contribute to pest invasion at homes. Some of these are: 

  • Overwatering plants 
  • Inadequate ventilation 
  • Food crumbs  
  • Heating units 

This implies that although running dehumidifiers can help reduce bugs, you need to take other pest control measures to prevent them from invading your homes. 

Relationship Between Bugs and Humidity

Most pests and insects live in high temperatures and moisture conditions. Here’s why: 

  • High precipitation provides a favorable environment for insect breeding. Studies have found a significant effect of relative humidity on egg hatchability.  
  • In humid areas, during rainy conditions, puddles often form and create an ideal environment for insects to inhabit and grow in the stagnant water. 
  • Insects like roaches and ants look for food and dry ground in homes during wet weather. 

Typically, most bugs are seen indoors when the humidity level exceeds 70%. However, these levels can vary for each type of insect. 

Common Bugs Found In High Relative Humidity Conditions 

The following table illustrates some common insects that invade homes in the wet season. 

InsectHarmful Effects
SpidersSpiders have poisonous bites that can cause various complications ranging from pain and swelling to edema, respiratory problems, hypertension, kidney dysfunction, etc. If not treated promptly, some spider bites can also result in death. 
Silverfish Silverfish are not poisonous but can act as vectors for germs and contaminate food. 
Roaches Roaches do not carry disease but can carry germs that may cause gastrointestinal tract (GIT) issues, typhoid, poliomyelitis, etc.  
Ants Besides painful ant bites, ant infestation may result in the spread of various bacteria. 
Bedbugs Bedbugs cause itching and skin infection, and general discomfort during sleep.  
FleasFlea bites can cause allergic reactions, swelling, itching (especially around lips and face), nausea, etc. 
Gnats Gnats aren’t particularly harmful to people, but they significantly damage plants.  
Centipedes Centipedes carry venom that can cause anaphylaxis and cardiac ischemia. A centipede bite can also cause neurotoxicity (disruption of the nervous system). 

Considering their effects, it is crucial to remove these pests from our indoor spaces. Dehumidifiers reduce moisture content, making the environment less conducive for pest survival and growth.  

It should be noted that dehumidifiers cannot eliminate or influence all bugs as some pests can endure low humidity.  

How To Prevent Insects In the Basement

Most American and Canadian houses have full basements. Though basements are essential in areas subjected to extreme weather conditions, tornadoes, heavy rainfall, etc., they can also harbor insects.  

In fact, basements are more prone to pest invasion than other parts of the house for the following reasons:

  • They are dark and moist  
  • Basements are mainly used as a storage area and can provide a steady food supply to bugs. 
  • Basements are usually not cleaned regularly, and the dust buildup can further exacerbate the pest population. 
  • They are poorly ventilated, and the air quality (AQI) is often low. This allows a lot of airborne pathogens and insects to enter and inhabit the basement.  
  • Poor maintenance may lead to cracks in the basement wall., which acts as an entry point for bugs.  

Spiders, roaches, mosquitoes, termites, and ants are the most common insects in basements. 

These basement insects can easily make their way inside the home through plumbing pipes and cracks.  

If you frequently encounter bugs in the basement, we recommend investing in a whole-house dehumidifier if possible. They provide extensive coverage and can be installed in the basement. Since the basement is the most humid area of a house, placing a whole-house dehumidifier prevents the ideal conditions for bug infestations from establishing anywhere in the home.

Apart from installing a dehumidification system, here are some other practical measures you can take for insect control: 

  • Reduce clutter 
  • Vacuum regularly 
  • Cover cracks and drains 
  • Keep only packaged and sealed food in the basements 
  • Install an air purifier to minimize exposure to airborne pathogens  
  • Use a CFL (yellow light) bulb  

How Long A Dehumidifier Should Run For Pest Control

In high moisture areas, it is best to run a dehumidifier 24/7. However, this is often impractical considering the energy costs.  

Therefore, operating a dehumidifier for a minimum of 12 hours is recommended. In the case of a newly purchased appliance, you need to leave it for a more extended period, as it typically takes 10 to 12 hours to bring about a significant difference in humidity levels. 

Which Dehumidifier Should You Purchase For Bug Control?

There are three main types of dehumidifiers, each of which is most effective in a particular climate. Therefore, purchasing a dehumidifier suitable for your weather conditions is crucial for efficient pest control.  

The primary types of dehumidifiers are: 

1. Compressor Dehumidifiers

Compressor or “refrigerant” dehumidifiers have a conventional construction and are therefore known as legacy dehumidifiers. 

A rotating fan draws air inside the unit and passes it over cooling coils which condenses the moisture in the air. While the collected water is transferred to the hose, dehumidified air is dispensed out of the system. 

Compressor dehumidifiers are perfect for high temperatures. However, in cold weather, compressor dehumidifiers fail to perform as the weather is colder than the temperature of cooling coils.  

2. Desiccant Dehumidifiers

Desiccant dehumidifiers use a silica gel or sponge to absorb moisture. Unlike typical units, desiccant dehumidifiers work efficiently in all temperatures. However, they too should not be operated below 60°F. 

3. Whole House Dehumidifiers

While compressor and desiccant dehumidifiers cater to only a particular area of the house, whole-house dehumidifiers can cover the entire house, and are typically constructed using compressor or refrigerant technology.  

Warm air currents enter the system via a rotating fan. The air comes in contact with the cooling coils causing condensation of the water vapors. The warm but dehumidified air is removed from the unit. While the water removed from the air is collected into a reservoir that is usually drained via a drain hose and pump.

How Do I Permanently Get Rid Of Bugs In My Basement?

Installing a whole-house dehumidifier is essential to deterring bugs in basements. Regularly sweeping and vacuuming the area, storing only sealed foods and items in the basement, and blocking all potential areas of insect entry (cracks in the walls, open drains, etc.) are also crucial.  

Pests in the basement are caused due to heat, humidity, and darkness. Controlling these three major factors can significantly reduce the insect population in the basement. In addition, since many plants attract insects, removing all plants from the storage area can help prevent bugs. 

Getting a professional to spray pesticides all around the house at the beginning of the rainy season is also a practical step to deter insects.  

Do Humidifiers Keep Bugs Away?

Humidifiers increase moisture levels and are not particularly effective in keeping bugs away. A humidifier may provide sufficient humidity to attract certain types of insects.

Although one might think that increased humidity levels imply more insects, this is generally untrue as humidifiers only increase relative humidity to a specific range of 45 to 50%. However, any malfunction in the humidifying system may impart excessive moisture to the environment, which can attract roaches and termites.  

Humidifiers take in dry air and release it as mist or steam, thereby increasing the moisture content of the room. Most humidifiers have a filter, but it is a generic filter with large pores that don’t trap a lot of airborne insects. However, if a high-quality filter is installed in humidifiers, it can trap a lot of bugs. 

For more information, Plentiful Air has developed a complete guide to the effect humidifiers have on bugs available here.

Theresa Orr

Theresa Orr holds a PhD in Earth Science and specializes in determining past climates from rocks using geochemistry. Her passion for clean water, soil and air drives her to provide easy to understand information for everyone to read.

Recent Posts