Are higher quality air filters worth the extra cost? In general, the answer is yes. More expensive air filters are more effective, but the amount of filtration needed depends on the individual's circumstances. For instance, a single person without pets and allergies may not need as much filtration as a family of five with three pets and a child with asthma. Washable air filters are an attractive option because they should last for years instead of months.
However, they have some drawbacks, such as lower MERV ratings, frequent maintenance requirements, and the potential to attract mold to your air unit. If your HVAC system uses a coarser filter (usually in the 4 to 5 inch range, and typically mounted on the air handler), it's likely designed specifically for medium efficiency MERV filtration. A dirty or clogged air filter is never good for your HVAC system, and these filters should be replaced regularly. If you have a family member who suffers from respiratory problems or allergies, then it would be wise to invest in more expensive air filters.
Pleated air filters are more effective than their non-pleated counterparts because they have more folds (sometimes called pleats) that increase their surface area. This means more space to trap particles in the air. Not only do these filters remove dust allergens, mold spores, and other pollutants from the air your family breathes, but they also filter out fine dirt particles that can degrade the performance of the HVAC system itself. Your home's air filter blocks problems in the air that a ventilation system can pump from the outside.
However, proper domestic air filtration requires you to change your home's air filters regularly before you start seeing evidence that it's been a while since you changed them. Contrary to popular belief, pleated air filters don't make your HVAC central unit work harder because they allow more air to pass through. Expensive filters may seem like a luxury, but their role is too important to settle for lower quality filters. Recent innovations in air filters allow for high MERV ratings (11 to 1) with low pressure drop.
Air filters remove particles of different sizes from the air before the air flows through the blower to the rest of the house. Your home should be a place to relax and breathe easy, and air filters are the tools that help you do that.