Indoor air pollution is a top health risk facing Canadians in the workplace and at home. Canadians spend much of their time in their homes, particularly during winter. The concentration of pollutants and contaminants is typically worse indoors. This problem has worsened in recent years. Modern construction techniques allow for tighter seals and, thus, better energy efficiency. But the downside is less natural ventilation and often poorer air quality.

What Is a Whole-House Air Purifier?

A whole-house air purifier is a system that provides clean air throughout an entire living space. There are standalone air purifiers that can filter air even in large homes. What sets a whole-house air purifier apart is that it integrates into the HVAC system. You, therefore, do not need a separate air handler or blower. The system can also make use of the existing ductwork. There are other advantages beyond air purification and reduced costs. It helps to keep the HVAC system, including the ducts, clean. It also mitigates the negative IAQ impact of central heating and cooling.

Many different brands and models of whole-house air purifiers are on the market. What typically defines these configurations are the stages that they comprise. The common stages available are:

  • Prefiltration
  • Mechanical Filtration
  • Absorbent Filtration
  • Ultraviolet Radiation
  • Photocatalytic Oxidation


Prefiltration is mechanical filtration, but it serves a different core purpose. The goal here is to trap large particulate matter. Large PM in this context consists of particles between 3 and 10 microns. Trapping these large particulates early in the stream protects the air purifier and other aspects of the HVAC system. It also helps to preserve the other filtration media. It is notable because prefilters tend to be inexpensive. High-quality mechanical filters are often one of the costlier aspects of maintaining an air purifier.

Absorptive Filtration

Most air purifiers on the market provide absorptive filtration. They achieve this with absorbent media. Manufacturers often position it ahead of the primary mechanical filtration. If applicable, it is typically between the prefilter and mechanical filter. Most air purifiers use activated carbon at this stage. This substance is also called activated charcoal. Activated carbon absorbs odors and thus helps to freshen the air. It will also absorb smoke, gases, chemicals, and volatile organic compounds.

Some manufacturers integrate their activated carbon into mechanical filtration. Higher-quality air purifiers tend to have a distinct absorptive stage. There are two main types in this regard. Fiber-activated carbon filters are thin fibrous filters similar to felt and manufactured with fiber-bonded carbon. Granular activated carbon filters are cartridges that have loose-fill activated carbon filters.

Mechanical Filtration

The mechanical stage traps the small PM most associated with air pollution. These are the particulates linked to many respiratory and cardiovascular diseases. Most air purifiers in Canada use a high-efficiency particulate air filter. HEPA filters are not unlike an HVAC air filter but have a much higher MERV rating. MERV stands for minimum efficiency reporting value and measures filter effectiveness.

The industry measures effectiveness as a percentage but also a size. HEPA filters have a MERV rating of at least 17. That means that it will trap 99.97% of all particles down to 0.3 microns in size. The Canadian grading system for HEPA filters also recognizes a medical grade. Many air purifiers support these filters, which trap 99.995% of all particles down to 0.3 microns in size. High-quality HEPA filters of all grades can last approximately 12 months with prefiltration.

Ultraviolet Radiation

Some air purifiers on the market have a UV stage. You can also add this filtration to your system with UV lights. This filtration process involves using ultraviolet light, or UV-C in particular. UV-C is a germicidal light. It neutralizes pathogens, bacteria, viruses, molds, funguses, and dust mite eggs. Recent studies have even shown UV-C to be effective at neutralizing COVID-19.

The effectiveness of UV purification depends on several factors. The material quality of the emitter bulb matters, as does the intensity of the light. Another critical factor is how long the air is exposed to the light. Most manufacturers recommend replacing their bulbs every 12 months.

Photocatalytic Oxidation

The industry uses the term air scrubbing. It often refers to photocatalytic oxidation. Typically, manufacturers will combine the PO and UV stages. We’ll discuss it separately here because it serves a different purpose. Using a titanium dioxide catalyst, for instance, an air purifier can charge particles. Those reactive electrons then bond with VOCs, bacteria, and so forth and neutralize them. It occurs not only in the air but also on surfaces.

The Health Benefits

Air purifiers allow for easier, cleaner breathing. It results in a healthier environment with both short- and long-term benefits. People who live in air-purified environments are less prone to illnesses, allergies, heart disease, asthma, and other respiratory conditions. Those with allergies or asthma suffer symptoms less often, and those symptoms tend to be less severe.

If you experience restless sleep, using purified air can improve sleep. People are less likely to experience headaches, muscle pains, and chronic fatigue. Research shows that poor indoor air quality exacerbates the effects of old age. It also has a more significant negative impact on children. Studies show poor IAQ results in decreased school performance and slower social and emotional growth.

Whole-Home vs. Portable Air Purifiers

A whole-home air purifier provides clean air throughout the entire residence. Most Canadian homes need multiple portable air purifiers to provide the same coverage. You could use a portable air purifier in your immediate space. While better than no air filtration, it doesn’t offer the same overall health benefits. You’ll also have fewer configuration options.

Portable units are less expensive, at least initially. Whole-house systems tend to be less expensive over the life of the equipment. The filter media tends to be cheaper in the long run, too. Additional maintenance is required. But your technician can do that during your autumn HVAC tune-up.

Area, CFM and ACH

Manufacturers rate air purifiers primarily in three ways. The area measurement will be in either square meters or square feet and is the total coverage provided. Cubic feet per minute tell you how much air the system moves. Air changes per hour tell you how many times all the air is cycled. The industry recommendation is a minimum ACH of five. You should consult with your doctor if you have allergies, asthma, or other medical conditions.

Local Iaq Solutions in Nanaimo

If you live in Nanaimo or the surrounding areas and want to install a whole-house air purifier, Twin Peaks Plumbing, Heating & Gas is here to help. We have many years of experience installing air purifiers and UV lights. Our technicians install, maintain, and repair all ducted and ductless heating and cooling manners. We also have plumbers installing tank and tankless water heaters, cleaning drains, detecting leaks, and more. Call Twin Peaks Plumbing, Heating & Gas today to schedule an appointment or with any further questions about our products and service.

company icon