How To Trim Return Air Filter

How To Trim Your Return Air Filter in a 8 Easy Steps.

This quick project took hardly anytime at all and really makes an eyesore much more attractive. With only a few tools and materials this took a few hours from start to finish.

With so many scrap pieces of Drip Cap molding laying around after the ceiling project, door and window trim I decided to keep it cohesive and use it to trim out our return air filter. I purchased these from a local overstock warehouse for $2.00/stick.

Step 1 Measure and mark trim:

Custom return air filter trim step1

I marked the trim on each end where my outside angle cut will start, also adding a cheat mark as a reminder which way the angle will go.

Repeat for all for sides of return air filter.

Step 2: Cut trim using a miter saw.

Custom return air filter trim step 2

I laid flat on its “back” with the thicker part of the trim toward the back of the fence. Turn to a 45 degree angle and cut.

How To Trim Return Air Filter

Turn the saw to the opposing 45 degree angle to cut other end of trim

Repeat for all four trim boards.

Step 3: Paint

Custom return air filter trim step3

I paint my trim before attaching to the wall to avoid getting bright white oil based paint on my blue wall. You can add this step to the end of the project if you use water based paint for your trim.

Step 4: Clean and change filter 

Custom return air filter trim step4

Might as well clean and change your air filter if you are going to the trouble to give a facelift! Using rubbing alcohol and a small dollar store scrub brush, I got all of the caked on sawdust off of this grate really fast.

Step 5: Attach trim to the wall

Custom return air filter trim step5

Using an 18 gauge pneumatic nail gun and 2″ finishing nails, I attach all four pieces of trim to the wall.

Step 6: Fill nail holes with your favorite wood filler.

Custom return air filter trim step6

18 gauge finishing nails hardly leave a hole at all, so this step goes by very quick.

Step 7: Caulk

Custom return air filter trim step7

There were very few gaps between the trim and the wall but I caulk everything, possibly overkill…

Step 8: Touch up surrounding paint

Custom air filter trim step8

Return Air Filter Before

Custom air filter trim before

Return air filter with custom trim after

Custom air filter trim after

I shared this project as a video on my YouTube channel. Since I only took video of the project that is the reason I am in every picture 🙂 Recently I learned how to save parts of my videos as a picture or .jpg So I went back through the video so that I could share this project with my blog friends. Hope you enjoy it!

You can watch the full video for a little more description of each step:

I hope you will come back for future projects, subscribe below and we can keep it touch.

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If you do not have an overstock building supply warehouse nearby you can always use my affiliate link to purchase from Home Depot.

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