How to Make a DIY Cornice Board

This tutorial on how to make a DIY cornice board is a no-sew project made with styrofoam. It's as easy as gluing and taping a few things in place!

how to make a no-sew cornice board.

Well, my baby is officially in a big-boy room. It hasn't been as difficult of a transition as I thought it would be - he absolutely loves it, and I'm (a little begrudgingly) ok with not having a crib in the house anymore. When we finally put a big boy bed in his room, he helped us picked out a super cute car/train bed in a bag set for his bed. I totally wanted him to have what he wanted - even if the comforter is a little loud for my taste. 😉 It does have gingham in it, which I'm absolutely obsessed with, so I was ok with that part.

We can't put a bed skirt on his bed because of the way it's made, and the set didn't come with any kind of window covering, so a few days after we got him all set up, I had an idea: why not turn the extra fabric from the unused bed skirt into some kind of cornice board? It wasn't enough fabric for any other kind of curtain, but I thought a fabric-covered cornice would be just perfect for his room. I just love how it turned out - I thought I'd share how I whipped it up!

blue gingham cornice board on a window.

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To complete this project, you'll need...

Insulation Foam Board (If you can find 1.5" thick like this one, this would be even easier. My store didn't have it, so I went with .5" thick and just triple-layered it.)  One of these boards is easily enough to make 2 cornice boards for standard-sized windows!

E6000 Glue

Sharpie and Sewing Ruler

A good, sharp Utility Knife

Duct Tape

Stapler

Quilt Batting

Fabric (for both front and back of board)

Hot Glue Gun

Inexpensive Curtain Rod

piece of polypro foam board.

Start with a big sheet of foam insulation board, which can be found at most home improvement stores. These typically aren't super expensive, are much lighter than using wood for this project, and are much easier to cut/attach!

quilting ruler on top of foam board.

You'll construct the frame of the cornice out of three different sides of foam. The first (front) one should be 5" wider than the outside of your window frame and, depending on your preference, somewhere between 11-14" tall. I went 11" to fit my fabric, but it's almost a little small - I'd personally recommend closer to 14".

The two side pieces should be 5" long by however tall your front piece is.  My front piece was 11" tall, so my two side pieces were 5x11".

cutting into foam board with a razor blade.

Because I wasn't able to get my hands on the 1.5" thick board, I had to kind of build my pieces up. I cut three pieces of each of my 3 sides and glued them together like a sandwich with E6000. Using my sewing ruler and a sharpie to measure these out made sure my pieces were nice and square.

long rectangular piece of foam board.

two rectangular pieces of foam board.

The pieces might look a little jagged when first cut, but it's ok - you can always go back and even them out after gluing. Let this dry, then...

quilt ruler and razor blade on top of foam board.

Using that sewing ruler as a guide, go around and cut any jagged pieces off. (The whole cutting process makes a huge mess, so I'd do this outside if you can.)

frame of cornice board made with foam board, duct taped together.

Then, simply duct tape your frame together. The side pieces should sit behind the front piece (if that makes sense) when taping.

frame of cornice board made with foam board, duct taped together.

Next, attach your quilt batting! This is what gives the cornice board kind of a fluffy, pillowy look.

stapling batting onto foam board.

Your piece of quilt batting should be cut to 16" wider than your front piece and 4" taller than your frame. Once cut, I just tacked it in place with a plain old stapler...

back of cornice board, with batting duct taped in place.

Then duct taped it in place really well. This looks terrible right now, I know...we'll fix it before we're done.

Now, let's add the fabric. Your piece of fabric should be 1" wider (in both length and width) than the measurements you cut for the quilt batting.

back of cornice board, with fabric duct taped in place.

Start by wrapping it at one end, making sure your fabric is lined up correctly on the front and doesn't look over-stretched (but is tight). Duct tape it in place.

back of cornice board, with fabric duct taped in place.

Then, slowly, work your way down to the other side of the board, stretching the fabric into place and taping. Spot check yourself often to make sure the front looks ok before moving on.

back of cornice board, with fabric duct taped in place.

Finish it off by taping the other side just like the first one. Make sure none of your tape is sitting too close to the edge of the frame.

rotary cutter, quilting ruler on top of piece of fabric.

Then, use another piece of fabric as your back cover. Most likely, nobody will notice the back of the board, but I hated the thought of seeing duct tape sticking out of mine - so I just glued a piece of fabric in place to cover all of it.

Use a measuring tape to measure the inside of the back of your frame. You want to get it pretty close (maybe within ½") of the edge, but not over. I used some leftover outdoor fabric I had from our outdoor sectional project, and it worked wonderfully - no pulling or fraying at all!

fabric draped over back of cornice board to cover tape.

Set it inside of your frame to make sure it's the right length, then simply hot glue the outside edges in place.

right side of cornice board with curtain rod in place on the back.

Finally, you'll need to add hardware to hang the cornice board. This shouldn't be heavy at all, so a cheap-o white curtain rod (this one was a dollar) should work just fine.

cornice board with curtain rod in place on the back.

Position it in place to where the end (that will touch the wall) is flush with the part of the cornice board that touches the wall. You might need to stack something underneath to hold it in place - if you happen to have published a planner in the past few months and haven't thrown away the hundreds of proofing pages yet, those work pretty well. 😉

Just glue the sides in place with E6000 and allow the glue to set overnight. Then, simply attach the board to the wall with the hardware that came with the curtain rod!

blue gingham cornice board on a window.

I'm telling you - it doesn't get much easier than this. You'd never know that this is held together with hot glue and duct tape. 😉 I think it's such a cute piece that's perfect for a child's room!

More DIY Projects

Check out more of my DIY projects by clicking here!

xo, Leslie - blog post signature at the end of post.

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2 Comments

  1. Brilliantly darling! My kind of project!!! Duct tape and glue......yay!!!!!

  2. Hi Leslie, This turned out great! laura