Genesis School of Natural Health

DIY Air Cleaner

Have the pollens gotten you down?

Do you cringe at the thought of spending thousands of dollars for a professional-grade air-cleaner system?

Well, you’ve come to the right place. Keep reading to learn how to make a very affordable, yet effective DIY air cleaner for around $30. You don’t even need to be “handy” to rig up this simple air cleaner system.

To inexpensively keep the air in a room 90% cleaner than it is right now, one box fan with a high-quality furnace filter can make a significant difference in a small room like a bedroom with the door (and windows) closed.



Start with a standard 20” x 20” box fan.  Walmart currently has the Lasko 20” box fan for $22.46.  The brand isn’t important, as any standard 20″ box fan will do.  Chances are, you may already have one.


Next you’ll need a 20” x 20” x 1” MERV 13 HEPA furnace replacement filter. The height and width are significant to get the best fit for your 20” x 20” standard-size box fan.

A MERV 13-rated filter is effective for reducing pollen, dust mites, sanding dust, textile and carpet fibers, mold spores, dusting aids, cement and lead dust, Legionella, humidifier dust, milled flour, auto emissions, all bacteria, most tobacco smoke, droplet nuclei (from sneezing,) and more…

The least expensive brand we’ve found with the MERV 13 rating is listed on a package of 6 filters on Amazon. The price is currently $47.50 and comes with free shipping. That is just $7.92 each!

The local hardware store will likely carry this size furnace filter, so the brand is not important, however, the MERV 13 rating is. We were simply looking for the least expensive options that are also easily accessible for most, especially for those households that require multiple DIY Air Cleaners.

It is recommended that you change your DIY Air Filter a minimum of every three months. At this rate, a package of six will last one fan application a full year-and-a-half.

In high-allergen seasons or situations it will be necessary to change the filter more frequently, even monthly. One may expect this to vary according to each individual’s needs and situation.

HINT: Write the ‘3-month change-out’ date (or monthly, whichever you prefer) on the new filter when attaching it to the box fan. Then write the date in your planner so you won’t forget.


Attach the sides of the filter to the back of the fan with duct tape. Run a strip around the sides of the rear sides of the fan and edges of the furnace filter. Make sure that the air from the room can only enter from behind the filter to capture the pollutants in its fibers. If there is room for air to enter the back of the fan around the sides of the filter, this style of air cleaner will be much less effective.


Close the door, turn on the fan and… BREATHE!

This simple system works great in average-sized bedrooms. In a smallish one-bedroom apartment a minimum of two fans would be recommended to provide a better result. Larger homes and spaces will require more Air Cleaners.

To obtain optimal air quality allow the fan with the filter attached to run for about half-an-hour in a closed system. An air particle counter can be purchased to measure the actual effectivity of the air cleaners used in the various areas throughout the home or office.

Thank you for taking the time to read out this DIY Health Tip. If you like this idea or have found ways to improve upon it, please let us know in the comments below.


For further explanation and demonstrations watch this:
or this:
or even this:

MERV filter ratings info, read this:

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