Are all HVAC air filters the same? No, HVAC air filters vary due to quality and size, and some have specs that others don't. Mostly we recommend installing the filter your HVAC manufacturer recommends pairing up with your installed equipment, though you could be tempted to try a different filter type for convenience or to remove more pollutants from your home. Filters have MERV ratings, which range from 1-20. MERV is an acronym for "minimum efficiency reporting value". A higher MERV rating equates to fewer particles pass through, and it captures finer particulates. This seems obviously good, and it can be, but a filter that eliminates finer dust and allergens will also stop up faster, and pressure on your HVAC equipment will rise. If your system has not been engineered to operate with this kind of filter, it can actually reduce your airflow throughout your house, affecting your comfort and energy expenses. So what should you do? Unless you live in a hospital, you probably don't need a MERV rating above 13. Truth be told, most residential HVAC systems are specifically designed to work with a filter with a MERV rating below 13, and frequently you will discover that higher end systems have been made to function with a MERV rating of 8 or 11. All filters with a MERV rating of at least five should eliminate most of the major nuisances everyone cares about such as pollen, pet dander, and dust. While some filters claim to be able to catch mold spores, we recommend hiring a pro to clean out any mold from your residence you find, instead of trying to delay the issue with a finer filter. Usually the packaging shows how often your filter should be replaced. There are one-month filters and there are 3-month filters. Additionally we have filters that are two dimensional, flat screens, and you have some that are ridged with supporting wire. In our experience, the accordian style filters fare better, and are worth it for the extra durability. You may also consider washable filters, also known as reusable filters. Some homeowners like the environmentally friendly aspect of it, because they don't add to a landfill, and others think it more convenient to quickly yank out the filter and clean it off rather than making a special run to the local hardware store for a filter of the correct size. These filters are often created to last several years and will save you money over those years, though they cost more initially. However, washable filters have to be dried out one hundred percent before inserting it back to prevent mold growth in your vents. In addition, most washable filters typically have a MERV rating between 1 and 4, and they lose their efficiency over time. Some washable filters have been built with new technology, such as electrostatic air filters, that are meant to essentially improve the MERV rating. Last, filters are built with different materials. Fiberglass filters are what is commonly used, and are the disposable type. Polyester and pleated filters can catch more debris, but also reduce the airflow in your home. And there are high efficiency particulate arrestance filters, or you might recognize the acronym HEPA. While you may be tempted to buy a HEPA filter, just understand that's like putting a MERV 16 filter in your HVAC system and it's highly unlikely that your system was constructed to handle that kind of resistance. Back To Frequently Asked Questions