DIY Window Mullions | How To Add Grids To Windows

Get ready for the best hack for DIY window mullions! Over the last year I have completely fallen in love with black grid windows (also called window mullions!) When we moved into our home, it already had these stunning french doors that we painted black. Then last year, we worked with Cougar Windows and Doors to add the black mullion windows above the french doors which changed the space SO much!

The Best Product for DIY Window Mullions

Last week, I watched Mallory add faux grids using vinyl stickers and I knew I had to give this a try in my kitchen! Mallory’s mother in law has a vinyl sticker shop (Cali Mom Designs) and was able to make the perfect shape for this project!



This project turned out to be so simple! All I did was measure to find the center of each window, then marked the grid with a dry erase marker. I used a level to make sure I drew a straight line!

I decided to do a diamond pattern on the top to match my backsplash and to avoid having mismatched center lines. The two windows in my kitchen aren’t perfectly center and I didn’t want to draw attention to that!

How Do They Look?

Even up close, the grids look so great and it is hard to tell that they are vinyl stickers! I love that I’m able to preserve my windows while still achieving this trendy look!



  • Reply
    April 11, 2021 at 11:43 am

    Amazing project. I have a huge picture window in our living room I’d like to try this on. Thanks for the idea.

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    April 12, 2021 at 11:35 pm

    […] My latest project: DIY Window Mullions! […]

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    Home Care
    May 19, 2021 at 12:35 am

    That’s something I’d want to check out. Thank you for the idea.

  • Reply
    August 3, 2021 at 4:32 am

    They look amazing! I love the diamond pattern in kitchen. I just did the same thing to mine using electrical tape to see how they would look.

  • Reply
    August 11, 2021 at 10:32 am

    Wow! This is an unique and stylish way to make a wonderful window design. I have seen this for the first time. I am going to add this in my itsupport office https://www.itsupportcell.com/ where people get IT related support. Is there anyone else like this? Who is thinking as I am thinking.this is amazing!

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    August 22, 2021 at 12:23 pm

    Your large window looks amazing. A chic interior and maximum natural lighting. The main thing is that it provides you with reliability and noise insulation, I also found these for myself here https://blueskywindows.com.au/double-glazed-windows/

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    January 17, 2022 at 2:29 am

    Thank you so much to sharing amazing post.


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