Electrostatic Air Filters: Yay or Nay?

Posted on: 8 May 2017

There are many kinds of air filters available for your HVAC system. The end goal of each one is to filter the air in your home and keep it as clean as possible by trapping dust, allergens, and other tiny particles.  A clean air filter extends the life your HVAC system as well. Electrostatic air filters are washable air filters that never need replacing. Take a look at how this type of filter works, and what the pros and cons are of using one in your home.

How an Electrostatic Air Filter Functions

Instead of cloth netting or pleats inside traditional air filters, electrostatic filters have several layers of vented metal. As air passes through each layer, air molecules become positively charged by the friction of their movement.  In doing so, dust, pollen, and other particles become trapped within the many layers.

Each month, you remove the filter and clean it using a variety of methods. Some people prefer to vacuum it first to remove larger particles, and then spray it with a garden hose. Others soak it in a bathtub and use a detergent to clean the filter. Still others place the filter in their dishwasher. Once the filter has thoroughly dried, you simply put it back in the furnace. Whatever the method you use, you simply reuse the same filter and do not throw it away.


The biggest draw for consumers is the fact you never have to buy another filter for your HVAC system again. It can be a hassle to remember to purchase conventional furnace filters each month. Ever stand in front of the filter selection at the store, trying to remember which of the 20 available sizes you need? You purchase a filter just rarely enough that it's difficult to recall your size.

And speaking of purchasing filters, the average price for an electrostatic version pays for itself in just a few months. The average price for one ranges from $30–$70. An inexpensive, standard filter costs about $3, but quickly rises in price to $25 for top-of-the-line allergen filters. You end up saving money once the filter has paid for itself.

Finally, you can feel a little better at keeping old, discarded furnace filters out of our planet's landfill. Conventional filters are made of paper, cardboard, and woven polyester or fiberglass fibers. Much of the filter is biodegradable and breaks down over time in the landfill. However, fiberglass does not. In fact, many types of fiberglass contain formaldehyde. Once in the landfill, fiberglass can release this dangerous toxin into the air. Tiny fiberglass particles can cause rashes, tiny cuts, and other health problems if inhaled.


One of the biggest downsides to the electrostatic filter is its high initial cost. If you're used to paying a mere $3 for a cheap throw-away filter, then $35 can be a tough investment to swallow. Most electrostatic filters can only be purchased online, which may or may not be convenient while you wait for shipping.

Then there's the issue of washing the filter when it gets dirty. You may feel a bit unsure you are washing it correctly or damaging it. This monthly chore can take a while depending on what method you use to wash the filter. If it is not completely dry when you re-install the clean filter, you run the risk for mold growth.

Because an electrostatic relies on static electricity to trap particles, it is strong enough to trap smaller, lighter particles. Larger particles may or may not be filtered properly, nor extremely fine bacteria or mold particles.  If someone in your home suffers from asthma, an electrostatic filter simply will not perform as well as a high-quality HEPA filter with a 1200 MPR.

Now that you understand how an electrostatic air filter functions, and you know the pros and cons, you can better decide if this type of filter is right for you. To learn more, contact local furnace installation services.