Builders seal homes more efficiently today than decades ago. They do so to save on utilities—less air leakage means less money spent on heating and cooling. Unfortunately, these energy conservation efforts introduce ventilation concerns. If air cannot escape then pollutants can thrive unabatedly.
How Ventilation Systems Remove Pollutants from the Home
We bring various pollutants into our homes without realizing it. When we cook, paint or sand, for instance, we release a bevy of particles into the air. Thus, ventilation is necessary to remove them and replace the contaminated air with fresh air.
By default, most HVAC systems do not mechanically bring in outdoor air. This means that you must rely on natural methods like opening windows and doors to let stale air escape. That said, modern systems now incorporate ventilation and filtration mechanics to improve indoor air quality and recover lost heating and cooling during the exchange. You can install such mechanics on existing HVAC systems, too.
Types of Ventilation Systems Available to Homeowners
You can install two types of ventilation systems: spot or dilation. Spot ventilation systems use exterior exhaust fans to expel pollutants and humidity from isolated spaces. For example, spot ventilations systems commonly appear in bathrooms and kitchens. Although some spot systems come with time and de-humidistat controls, most are switch-operated.
Dilute ventilation systems improve the indoor air quality of all living spaces. The effectiveness of the air exchange hinges on the cleaning mechanics—filters and dehumidifiers. Such additions make the biggest difference compared to natural ventilation efforts, as mentioned above.
Air exchangers and purifiers remove environmental contaminants from the home. An exchanger exhausts stale air from inside and replaces it with fresh air from outside. Conversely, a purifier detoxes the existing air, making it supplementary to a ventilation system—not substitutional.
How Purifiers Detox Indoor Air
Purifiers, known also as air cleaners, use fine filters to catch airborne irritants and contaminants. They suck said particles in, then release the cleansed airflow back into the room. Most purifiers use at least two types of filters. For instance, High Efficiency Particulate Air (HEPA) filters trap 99.9% of particles larger than 0.3 microns.
An example of when a purifier works its hardest is in a smoking or pet-friendly household. Most are capable of ridding the home of harmful second-hand smoke and dander. Understandably, a good purifier can help someone suffering from respiratory problems and/or allergies.
How Exchangers Bring Fresh Air into the Home
Regardless how efficient the purification system, homes need a fresh air supply. Air exchangers do exactly this: they exhaust old air and bring in new air. They use ductwork to create an airflow between the outside and inside, using a variety of components and technologies to regulate it.
Without ventilation, modern homes trap too much humidity and pollutants. This can contribute to mold and mildew growth over time. Interestingly, air exchangers even promise financial gains in the summer and winter. Exchangers can recover warmth/coolness from the exhaust and thus save on energy. This is another differentiator between exchangers and purifiers: purifiers do not contribute to the heating or cooling of a space.
When most of us hear about air pollution, we assume it concerns the outdoors. Yet pollutants are just as common indoors—and often more concentrated. Chemicals like lead, formaldehyde and radon come from cleaners, scents and appliances while other irritants like dust and dander accumulate between cleans naturally.
Only once we recognize that these pollutants exist can we begin to eliminate them. Largely, there are three methods for improving air quality: source control, ventilation and purification.
Source Control Strategies
Source control deals with eliminating or mitigating pollution origins inside the home. For example:
- Maintaining humidity levels between 30 and 50 percent can keep dust mites and mold from flourishing;
- Avoiding synthetic fragrances and air fresheners can prevent exposure to volatile organic compounds (VOCs);
- Using VOC-free adhesives, finishes, paints and varnishes can reduce toxic exhaust.
Source control may also deal with significant renovations to remove mold or asbestos and eradicate pest infestations.
Ventilation Systems and Windows
Bringing more outdoor air inside dilutes pollutants and expels stale air. Most HVAC systems do not bring enough fresh air into the home unless equipped with the proper mechanics. Therefore, something as simple as opening the windows on a nice day can help improve your indoor air quality. Plus, this can save on your energy bills.
Air Purification Systems
You can buy air purifiers to filter pollutants in the home. There are various types and sizes of air cleaners—some more effective than others. Most entry-level machines only suck particles from the air and not gaseous pollutants.
When assessing the efficacy of an air cleaning system, weigh two metrics: how efficiently it collects pollutants (percentage) and how much air it takes in (cubic feet per minute).
In addition to a purification system, buying green plants can contribute to cleaner air. That said, this green approach should merely bolster other efforts.