It’s no secret that indoor air can be more polluted than outdoor air due to modern, energy-efficient home building techniques that can seal a home’s envelope pretty tightly. One key to cleaning indoor air is proper ventilation added to remove polluted air and bring fresh air inside.
Sure, the very best way to accomplish whole-home ventilation is to open every window in the house, but that’s simply not possible 365 days a year. Instead, installing a whole-home ventilation system will bring outdoor air inside no matter what the temperature is outside.
In many cases, homeowners can choose one of four types of whole-home ventilation:
Exhaust ventilation system: Exhausts air from the house via a single fan connected to one central exhaust point while make-up air enters through leaks in the house’s shell and vents. Problematic in cold climates or areas with humid summers. Does not filter incoming air to remove pollutants. Simple and inexpensive to install.
Supply ventilation system: Almost exactly the opposite of the exhaust ventilation system. Uses a fan to blow outdoor air into the house while air leaks out through holes in the house’s shell, range fan ducts, and vents. Also simple and inexpensive to install. The supply fan generally is focused to direct air into the rooms that are most used in the house, such as bedrooms, kitchen, and living room. Allows outdoor air to be filtered before it enters the house so that pollutants are not introduced and humidity may be controlled, so supply ventilation may be a better option for those with breathing difficulties. Supply ventilation works best in hot or mixed climates.
Balanced ventilation systems require a fan to bring air into the home and a fan to exhaust air from the home. Because a balanced system requires two duct systems as well as two fans, it can be expensive to install. However, they are an excellent way to improve indoor air quality. Balanced systems work in all types of climates.
Energy recovery ventilation (ERV) systems control a home’s ventilation and minimize energy loss at the same time. None of the other types of systems consider energy loss along with the ventilation they offer. Energy recovery ventilation systems reduce heating and cooling costs by adjusting incoming air to the temperature inside the home by using a heat exchanger, fans to move the air, and controls. The simplest ERV shares ducts with the home’s heating and cooling system. ERVs are generally expensive to install, but can save utility costs to offset their price. Require regular cleaning to ensure that the ventilation rate stays consistent and the heat exchanger stays free of mold and bacteria.
Whichever type of ventilation system you choose, work with a certified HVAC contractor to ensure you’re installing the system that will best suit your needs.