Sometimes in the world of DIY, I manage to surprise myself. And let me say I am so proud that I managed to create this DIY cornice box on my own, with no actual plans to follow. I should warn you there are a lot of steps so this is going to be a long tutorial!
Last week I shared my oil rubbed bronze finish on my bath surround. This cornice has the same finish to tie it all together.
First let me say that this post contains affiliate links which help me pay for the site.
I used some non-traditional materials on the cornice box. The middle panels are not tin. They are foam core with paintable wallpaper glued on! I gave the whole thing my handy dandy oil rubbed bronze finish that I use on everything. You cannot tell, even up close that those panels are not tin. Not only was this cost effective, but it greatly cut down on the weight of using wood panels in there, and the cost of using tin. The curtain rod that is hidden inside the box was also non-traditional. I used a plastic plumbing pipe. It was $4 and I had enough left to make a rod for another window too! This also cut down on the weight of what turned out to be a very large cornice box.
I know sometimes scale is difficult to determine in photos. Especially because the room has tall ceilings. But this cornice box is over six feet long. It helped fill the empty space above the window. Before the window looked like it was hung too low. It had a huge space above that looked odd.
Let me start by saying that I really don’t know the right way to build a cornice box. I just knew I wanted one and it all made sense in my head. It actually turned out just the way I pictured it, which is not how these great ideas I have usually go. Typically I hit a roadblock or two along the way and end up rethinking things. The only thing I would do differently would be to come up with a better method to attach it to the wall. One that did not require three grown adults to contort themselves into uncomfortable positions or take two hours.
I started out by doing a lot of math. Yes, you heard right… that awful math thing again. I remember being in high school thinking I was going to be a graphic designer, what did I need math for? And the jokes on me because I have to use math and geometry every day in my job. In fact I probably use it more than a lot of people in other professions do. So thank goodness some of it has stuck with me over the years.
First I measured the window width. Then I measured the amount of space between my glass shower and the far wall. I knew it had to be smaller than the space between the shower and the wall but bigger than the window. Were it not for the wallpaper panels I could have just picked a size in between. But I did not want to cut off the wallpaper pattern in a bad spot and I wanted all three panels to be equal. So I measured the width of my MDF boards, and multiplied that by 4 (for the four vertical pieces) and then started measuring the wallpaper pattern. I had to figure out how many repeats of the wallpaper pattern I needed. So that plus the width of 4 MDF boards needed to be less than the distance between my shower and wall, and greater than my window width. I figured out the pattern would could repeat four times in each panel, and still fit into the desired area. After I got all the awful math out of the way, I cut out three equal panels of the wallpaper.
Next I took cheap dollar store foam core and following the manufacturers instructions, I adhered the wallpaper to the foam core. When it dried it warped. So I took a sponge, and wet the back and that helped flatten it out as the wallpaper shrunk when it dried, causing the panels to curl in the front. Then I put a bunch of really heavy books on it for a few days. And thankfully they were almost flat by the time I needed them. Obviously using wood would have caused less fiddling but this method was lighter and cheaper.
Follow the manufacturer’s instructions to soak the wallpaper.
Fold the wallpaper together glue side to glue side. This is called booking and it activates the wallpaper paste.
Once everything was dry I applied a coat of shiny black paint. After you let the paint dry it’s time to add the oil rubbed bronze finish. I poured some turpenoid onto a paper towel and added a dab of Rub ‘n Buff. Then I rubbed it over the raised area of the panels. See how it really brings out the details?
Apply turpenoid to the paper towel.
Add a dab of Rub ‘n Buff. A little goes a long way.
Finished adding the bronze to the panel.
Next I cut the wood. I made the height based on the wallpaper measurements. The width was the measured width of all three wallpaper panels and the four MDF panels.
This project used a miter saw and Kreg Jig. I have the cheapest version, it’s the little one, and it did everything I needed it to do. When you look at a pre-primed MDF you will notice one side has rounded corners and the other side has sharp corners. I wanted the sharp corners to be the side that faced forward, I created the pocket screw holes on the side with the curved edges. I attached the two outside edges to the top and bottom. Then I put the wallpaper panels down, put the outside frame on top, and made sure that the middle dividers were exactly where they were supposed to be.Basically I was dry fitting the panels. I marked them with a pencil, flipped it over and screwed the middle dividers in.
Kreg Jig pocket hole screws.
Finished pocket holes.
Once I had the front frame put together I worked on the side panels, without actually attaching them yet. I had to attach the curtain rod holder to the sides of the cornice box so that I could hang a curtain once it was up on the wall. I used a closet rod holder. I attached them to both sides and then cut my “curtain rod” which was actually a piece of PVC pipe. Cheap and light. It fit exactly right into the closet rod holder and was much cheaper than buying a wood or metal closet rod.
Add the brackets to hold the curtain rod.
With that complete, I finally added the sides to the cornice box. I used pocket screws and then reinforced it with L brackets because I was paranoid it would somehow loosen over time. I am pretty sure this was overkill.
Attach the side panels
Next came my crown and trim, which was a tiny piece of crown molding and a piece of screen molding attached underneath it. I love screen molding because it is inexpensive and gives a tiny bit of detail. I cut the corners on 45 degree angles and nail gunned it onto the cornice board.
Cutting the crown molding
Then it was back inside for paint. This is the same finish as I used on the panels above.
After finishing painting, I had to wait a few weeks for my father to come out to help me hang it. The hanging part was by far worse than everything else combined. Let’s just say that there were probably a lot easier ways for me to attach this, but at the time I didn’t know any of them.
I waited to attach the faux tin panels on purpose. This way we could access inside the box to attach it to the wall without having to go up from the bottom. It was hard enough to reach just to hold it up. This is a big cornice box. I attached L brackets along the edges of the cornice box. Then we held it up on the wall, centered and leveled it, and drew circles on the wall where the screws needed to go. Down came the cornice box. I removed the L Brackets from the cornice. Yes, I know this seems stupid, but I promise there is a method to my madness. I removed the L Brackets because there was no way to fit a drill inside the cornice facing the wall. You can however fit a drill sideways, which is where the L bracket attaches into the box. By doing it this way, my holes were already pre-drilled into the cornice box which means I knew it was going to be level when we lined up the holes. We were lucky that some of the screws actually went into wood. Drywall anchors were used on the other locations that did not have studs behind them.
Next I attached the faux tin panels to the cornice box with a staple gun. Finally I got to see it all together! I was so excited. My family, who had spent over an hour trying to help hang the thing, was slightly less enthusiastic about the project. Hanging it for the final time required three adults and a lot of contortions to reach inside and screw the screws back into the cornice box. One person held it, once person screwed it in, and one person had to hold up the flashlight to see inside. Did I mention we were all balanced precariously on the rim of my bathtub? And of course we did this after dark, with the blinds open. So when my neighbors drove in their driveway they were treated to a view of three grown adults balancing on a bathtub. I can only imagine what kind of crazy they think we are.
In then end my crazy hanging plan actually worked. The holes lined up, the cornice was level, and I love it! On a side note, I have since created more cornice boxes and have come up with a much simpler hanging plan. Those tutorials will be posted soon, and I will update this post with a link.
So here it is all completed! What do you think?
As you can see, I sewed some lined curtains. I like how it gives this rather masculine looking bathroom a feminine touch!
Thanks for hanging in there on this super long tutorial. I’d love to hear what you think!