A normal 1” filter will only filter large particles from the air - including particulates down to 10 microns, which is about the width of a human hair, but much larger than dust, pet dander, and other allergens.
They also get “clogged up” faster and can cause your system to work too hard and possibly wear out sooner due to debris that enters your furnace system. Filters have a standard rating system, MERV (Minimum Efficiency Reporting Value) that ranges from 1 to 16 (higher is better). 1” filters are typically a MERV 2-4 and are very ineffective at filtering your air.
MERV 11 filter standard with our installations
A step above this is MERV 16 filter
Unlike portable air cleaners, both of these will filter your home without producing ozone, a known lung irritant. Both will last up to 1 year depending on duct conditions, and will actually save you money on filters over the course of the year - which is a great benefit for you, because then we can change it for you when we perform your annual service on your system.