Home Ventilation Basics
Ventilation, the "V" in HVAC, is what keeps the air in your home healthy. Ventilation is important because a home without healthy air can exacerbate allergies and illnesses, as well as make perfectly healthy individuals feel less than great. Some estimate that North Americans spend more than 90% of their time indoors, and much of that indoor time is spent at home.
There are simple steps you can take to ensure that your home is being properly ventilated. Many HVAC systems come with ventilation systems, but they're not enough to provide balanced ventilation throughout your house. Other ventilation methods, such as exhaust fans in the kitchen, bathroom fans and attic fans, are all essential to keep your home moisture and bacteria-free.
While ventilation doesn't guarantee a 100% moisture and pollutant-free home, it can come close if you utilize proper ventilation methods. So take the time and have an HVAC contractor check your ventilation systems to make sure that a) you have sufficient ventilation throughout your home and b) all of the ventilation systems are working properly.
Benefits of Ventilation:
- Healthy circulation and balance of air
- Protection from air pollutants
- Excess moisture and heat stays under control
There are three main methods to ventilating a home:
1. Spot Ventilation:
This is also called intermittent local ventilation. Spot ventilation is needed throughout many rooms in a house, including a basement, kitchen and bathroom. You can find bathroom ventilation guidelines here.
2. General Ventilation:
Also called continuous whole-house ventilation. There are two types of whole-house ventilation systems that are commonly used in residential homes -- HRVs and ERVs. These systems often come built into HVAC systems, but they can also operate independently or be added to existing HVAC systems.
Heat recovery ventilators (HRVs), also known as heat exchangers, air exchangers, and air-to-air exchangers, bring in fresh air from the outdoors while exhausting stale air from the home, thus creating a balanced pressure system. An HRV system can incorporate small, separately switched booster fans in rooms throughout the house to control moisture or heat generated by activities like showering or cooking. It may be more energy-efficient for some homes to have a good quality HRV, as odors and pollutants can be quickly removed and the energy used to condition the air is recycled in the heat exchanger.
Energy recovery ventilators (ERVs) will modify the humidity content of the fresh air through the transfer of water vapor from one air stream to the other when bringing in fresh air from the outdoors and exhausting stale air from the home, thus creating a balanced pressure system.
ERVs are highly recommended in climates where cooling loads place strong demands on HVAC systems, like in Miami and Tampa. However, keep in mind that ERVs are not dehumidifiers, and dehumidifiers are an essential part of keeping your HVAC system running properly.
3. Vents & Ventilators:
Also known as attic and crawl space ventilation. Crawl spaces need to be protected from moisture that can lead to mold and bacteria growth. Moisture in a crawl space can also lead to structural damage.