Proper Ventilation Keeps Your Indoor Air Quality High and Humidity Down

Published on: February 15, 2015
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These days, homeowners are striving to make their homes as energy efficient as possible. But without proper ventilation, a tightly sealed, energy efficient home can quickly become stuffy and humid, and indoor air quality can plummet. Why? Because excess moisture and unwanted contaminants such as pollen, dust, or chemical residue from everyday home cleaning have no way to escape the home. Ensuring adequate air exchange is the key to removing the volatile organic compounds (VOCs), allergens, chemical pollutants and excess humidity that promotes mold growth.

Types of Air Exchange Systems

There are several mechanical ventilation system options that can help you ensure a healthier living environment with cleaner, fresher air.

  • Exhaust systems use a fan to exhaust stale indoor air to the outdoors. You may already have this type of fan installed in your kitchen or bathroom to help remove excess moisture from your home after cooking or showering. When an exhaust system is used to ventilate an entire home, the fan is typically located in the attic. As the fan pushes indoor air out, the home depressurizes and outdoor air is pulled in through passive vents and natural gaps in the home’s outer shell. While this is an efficient means of whole-house ventilation, there is a major drawback. Exhaust systems provide no means of control over the moisture and types of pollutants and contaminants that are being pulled into the home with fresh, incoming air.
  • Central fan integrated supply (CFIS) system that pull in outdoor air are often used in homes with a forced-air HVAC system such as a ducted furnace or heat pump. Working just the opposite of an exhaust system, a supply system uses the existing blower fan and ductwork, along with a dedicated, vented duct to bring fresh outdoor air indoors. A damper opens and closes the exterior duct vent, and a controller provides ventilation pulling in outdoor air as needed.
  • Ventilating dehumidifiers employ a fan to draw in outdoor air and distribute it through dedicated ducts. The air passes through a direct expansion dehumidifier to help remove excess moisture before it’s distributed throughout the home. This can be especially beneficial during more humid times of the year or in areas prone to higher humidity levels.
  • Balanced systems provide a means of supply and exhaust ventilation using two fans, separate duct systems and exterior vents to control the exchange of stale indoor air and fresh outdoor air. This balanced exchange helps prevent pressurization issues, which eliminates the risk of contamination from unfinished areas and allows for additional filtering. The opportunity for filtering also cuts back on the unwanted pollutants introduced from incoming outdoor air.
  • Heat recovery (HRV) and energy recovery ventilator (ERV) systems are essentially balanced systems with a heat exchanger. An HRV helps reduce energy costs by extracting heat from outgoing air and using it to warm incoming air. ERVs take this process a step further by also controlling the flow of moisture and keeping humidity levels at an appropriate level, which helps improve home comfort. During the long cooling seasons in the humid Southeast, an ERV is the most effective choice for controlling humidity and improving indoor air quality.

Other Ways to Improve Home Ventilation

Installing a new mechanical ventilation system will yield great results, but there are a few things you may be able to do right now using existing resources in the home.

  • Opening windows and doors in appropriate weather may not be the most high-tech way to improve ventilation, but it’s a tried-and-true system that works. Of course, you’ll want to keep in mind the current climate and air conditions when using this method since there is no way to control the humidity levels and the flow of pollen and other unwanted pollutants into the home.
  • Ceilings fans are an efficient means of keeping air circulating, and they can help boost heating and cooling efficiency when used properly.

If you need expert advice about the best ventilation option for your home, contact AirConditioningSouthEast.com for help finding a contractor in your area.