Some houses are wet houses, meaning there is high humidity in the structure. It may be that the house wasn't constructed properly or the moisture may be coming up from the basement, which is often damp. Homes located in the south where it's hot tend to be humid. This isn't good because humidity can result in rot and attract bugs. When condensation occurs in a house, bugs are drawn into the home because they are looking for water. Sometimes moisture condenses in the walls and you aren't aware of it until the house begins to rot noticeably.
The amount of water vapor that is in the air at any given time is humidity. When a home is humid it can cause people to have allergic reactions because there are organisms that thrive in humidity that people are allergic to. You may find yourself coughing, itching and sneezing because of these tiny water molecules. What you don't realize is that your bed clothing, surfaces in your home and counter tops are all ideal places for these organisms to live and thrive due to the high humidity.
When it is humid indoors this can prompt allergens to grow, which may cause the residents to suffer from asthma or rhinitis. Mold appears and dust mites grow when there is too much humidity in a house, notes Dr. Michael Ruff of the American Academy of Allergy Asthma and Immunology. Dust mites thrive when the humidity is 70 to 80 percent, notes Michael Potter, an entomologist at the University of Kentucky. The humidity in a house should ideally be kept at a maximum of 50 percent, if not lower. Use a humidifier gauge to determine how high the humidity is in your home. If it is more than 45 percent use a dehumidifier.
Swamp coolers can be used to reduce the moisture in a house. A swamp cooler consists of a water pump and a box-like frame and a motor that captures the moisture and forces outdoor air to go through filtering, water-soaked pads and cooling before the air is allowed into the house. This causes the warm air in the house to be pushed outside through vents or windows. The swamp or evaporative cooler provides continuous fresh air in your home
Vents and Carpet
Rooms where moisture is typical (the bathroom) need to be vented so moisture can escape. You may want to pull up your carpet and replace it with hardwood because carpet traps moisture and is the perfect place for dust mites to live.
Control your indoor humidity problem by opening doors, increasing the ventilation, using exhaust fans in the bathroom and kitchen, covering water pipes with insulation and making sure that your dryer is vented properly.