A lot of homeowners want to know– what should the humidity level be in their home? Whether your concerns are about mold growth, attracting dust mites and allergens, or if you just don’t feel comfortable in your home, getting your home in an optimal humidity range has a lot of benefits.

Ideal Humidity Range

The quick answer to the optimal humidity level question is that a home’s ideal humidity range is between 40% and 60%. Humidity in this range is most advantageous for controlling bacteria, viruses, fungus, mites, termites, respiratory infections, allergies and asthma, chemical interactions and ozone productions.

What happens when the humidity level is too high?

Other than just making you feel sticky and uncomfortable, high humidity can have negative effects on your home and your health. A home that is too humid can attract termites, which need humidity (as well as plenty of wood) to survive. It also creates the perfect environment for mold and fungus to grow. Microbial growth isn’t just a potential problem for your home, but also for any allergy sufferers living there. Those with allergies or asthma may find that high humidity makes their symptoms more severe, as well as attracting another common allergy trigger, dust mites.

Harmful pests aren’t the only lovers of humidity to watch out for—some bacteria and airborne viruses, such as chickenpox, thrive in humidity. Another health concern, although less common, is the increased interaction of humidity with chemicals found in your home’s atmosphere, building materials, and furniture (see chemical interactions).

What happens when the humidity level is too low?

Just like some airborne bacteria and viruses favor high humidity, others, such as the flu virus, favor low humidity (ever wonder why the flu goes around more often in the winter?). Humidity that is too low (just like humidity that is too high) can make symptoms of allergies and asthma worse. Low humidity can also make you more prone to respiratory infections and increase ozone production in your home which in high amounts can become an irritant (what is ozone production?).

Zero in on the best humidity level for your home

This chart can help you find the perfect humidity level for your home. If your concerns are to reduce the spread of viruses, the optimal level is right around 50%-60%. If you are trying to reduce fungi or dust mites, humidity 50% or lower is your best bet. If your family has asthma concerns, 50% is your optimal humidity level. Refer to this chart to find the ideal level that you feel most comfortable at and is also most beneficial for your health and home concerns.

Winter vs. Summer

In non-temperate climates, like Maryland, you may find different humidity levels for each season more comfortable and beneficial. In the naturally less humid winters, you may find a range between 50%-60% more comfortable. During humid summers, you may favor something in the lower range between 40%-50%.

If you think you may have a humidity problem in your home, you can test it with a hygrometer. Or you can call one of our experienced technicians to test it for you, and if there is an issue, we can give you an estimate free of charge for a partial or whole home humidifier or dehumidifier.

Schedule a Home Comfort Evaluation

Chemical Interactions
What does “chemical interactions” mean?
Chemical interactions refer to how water vapor reacts to things in your home and your home’s atmosphere that contain chemicals such as formaldehyde (found in composite wood from building materials and furniture), sulfur and nitrogen dioxide. Low exposure to these chemicals can cause allergies, skin, throat and/or eye irritation.

Ozone Productions
What does “ozone productions” mean?
This refers to indoor ozone levels. High humidity levels increase indoor ozone levels which then can cause eye and nose/throat irritation.

Sources:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1474709/pdf/envhper00436-0331.pdf