Sharing the full box moulding wall tutorial (with the math!) and full time lapse video of the picture frame moulding wall coming together! This tutorial is perfect for a beginner DIYer looking to add a decorative moulding wall to their space.
I’m so excited to share this DIY wall moulding treatment with you all! This turned out better than I’d imagined… and I’d imagined it would look pretty darn good. I’m so excited for where this room is headed and can’t wait to get to the decorating it!
This DIY feature wall is so beautiful. Whether you call it box moulding, panel moulding, picture frame moulding, or just a decorative moulding wall… it’s a great beginner DIY project as it uses the basic power tools (miter saw and brad nailer) and can be accomplished in just a weekend (or one day if you plan ahead like I did here!).
POST UPDATE: Since writing this tutorial in 2019, I’ve installed picture frame mouldings in four spaces and have some more tips to add!
This post was originally created in partnership with Home Depot Canada and Alexandria Moulding in 2019. It has since been updated and revised to answer frequently asked questions, this post includes paid and affiliate links. You can find all my policies here.
Since the 2019 post, I’ve since finished the reveal of this black bedroom space!
If you didn’t catch it, last week I shared the design board for our dark and moody primary bedroom makeover and this moulding wall is the first tutorial I’m sharing from the space.
We’ve done a lot in here since the ‘before’ when we bought the house and it’s time to finish the space up. The first things we took on were floors, baseboards and doors… and now the paint, mouldings and lights. But there’s oh so much more to go!
Besides decorating (what am I going to put on the other wall? And what about window coverings?! All the fun stuff!)… We have to pop the trim off the two old windows and order new ones (the seal is broken), I’m hoping to get a chair for our bay window (now that we have no dresser, there’s so much space!) aaaand would love to refresh our pillows- I can’t believe how beaten up they’re looking after just one year.
But before I get to any of that… let’s talk about this DIY moulding feature wall!
We loved having a dark and moody bedroom at our last house and the added dimension of the moulding wall in that room was something we wanted to do again… but different. And this? It’s everything I hoped it would be! We went with a black paint that I love so much and then added this modern but classic picture frame moulding with a minimalist trim profile.
We decided just to do the headboard wall of the master bedroom as a feature but to do the entire room would look amazing as well!
Today I’m sharing the full box moulding wall tutorial (with the math!) and full time lapse video of the picture frame moulding wall coming together!
Explaining the math behind laying out the picture frame molding wall is definitely not my strong suit but I wanted to make sure it was SO clear for you to be able to do this DIY project in your own home and the math is a big part of that.
How to calculate spacing for your DIY Picture Frame Moulding Wall Treatment
Once you wrap your head around it, the math for this DIY moulding wall is actually quite simple. Here’s how I did it (great for visual thinkers!).
I did all the math horizontally first, then did the math vertically second.
The first thing you’ll need to is measure the width of the wall and height of the wall. I like to do this in inches to keep the math straight forward. Keep in mind any old house is not perfectly square and level so most walls will have a small difference in length from the top of the wall to the bottom.
Then, decide is how many rectangles across you would like and your spacing. I decided I wanted 5″ between each rectangle (and around the edges) and 4 panels in total.
That means that I would have 5x 5″ spaces to subtract from my overall wall length. This is shown in the image below.
That remaining length gets divided into the four rectangles or boxes for the box molding.
This gives you the outside edge length of your boxes. You will be cutting these on a miter saw so the ‘outside edge’ part is important in a bit here.
Don’t want to do the math yourself? You might love this free cut optimizer!
Vertically, I wanted to have two boxes stacked with one larger than the other. We do have baseboard in the room so I measured the height of the wall minus the baseboard, then minus the 5″ space at the top, bottom, and in between the panels).
Then, I measured the height of my nightstands that I wanted the top edge of my bottom box mouldings to sit above and decided the height from that. If you don’t have furniture you’re working around, just go ahead and choose a height for your first box moulding.
Alright so in this case, my math was 96″ (wall height) – 4.5″ (baseboard) – (5″x3) (spacing) = 76.5, that gave me approximately 28″ for the bottom rectangles and 48.5 for the top rectangles.
It doesn’t matter how thick your trim is as long as you cut the mitres so that these lengths are the LONG edge. You’ve done your math on the outside edges of the rectangles.
How to plan your trim cuts to minimize waste
Did you know that planning what pieces you’ll take out of each trim piece can save you so much money on your DIY moulding wall? I often get questions about how much different projects cost me. While every month the price of materials change, the other factor is planning. I like to plan each cut to make sure I maximize each piece of trim. Here’s how I do that.
The first thing you’ll want to do is write down the pieces you need to cut. I’m going to use round(ish) numbers for the sake of making it easy to understand.
Say I needed 30″ lengths for the horizontal pieces, 2 pieces of that per box and two boxes in a stack would mean that I need a total of 16 pieces cut to 30″. For the verticals of the upper box, I need 50″ and I will need 8 pieces. For the lower box verticals, I’ll need 8 pieces cut at 28″.
If a piece of trim is 8 feet long (like this trim was), that gives you 96″ of trim. While you do need to account for a little bit of waste from where the saw cuts, you can account for multiple cuts out of the same piece of trim.
If I do some math, that tells me that I need 14 pieces of trim and this is how I should cut them:
- 50″+28″ (8 pieces of trim cut)
- 30″+30″+30″ (5 pieces of trim cut)
- 30″ (this piece would be used if I mess up on one of the other cuts as well)
If you’re having a hard time visualizing this, I like to draw out lines of trim on a piece of scrap paper and write the cuts I’m getting out of each one, crossing each piece that I need off once I’ve drawn it onto a trim piece. It helps my visual brain easily do the math and stop second guessing myself.
How to install a picture frame moulding wall
Once you’ve done your math, you can get to cutting your trim pieces and installing the picture frame moulding wall.
For the trim, I chose to use door stop from Alexandria Moulding at Home Depot Canada over classic detailed trim pieces that you would see in traditional picture frame moulding. This gives it a more modern feel that I’m totally loving.
If you want to a DIY picture frame moulding with a more traditional profile, I installed one in this dark and moody bedroom, one in this green bedroom, and one in this show bedroom.
This is a hit every time and I love how simple it is to pull together! Honestly there are SO many different types of trim available for you to create a picture frame wall moulding that suits your unique design style.
To cut the trim, you’ll want to use a miter saw.
There are other options if this isn’t a tool you have in your collection. If your moulding pieces are thin enough, you could use miter snips or you could use a miter box with a hand saw.
We have a miter saw with a saw stand that helps us go so much quicker though. Since you are cutting a lot of the same length pieces of trim, we chose to set up our saw stand with the guard in place for the measurements. This means that we could move quicker without measuring each individual piece with a tape measure. I like to cut all of my trim pieces before install.
To minimize waste, cut one miter as close to the end as possible, flip it around and hold the mitred cut against the guard as you cut the other end. Using the guard for your measurements helps the cuts go so quickly!
Keep in mind that the miter cuts need to be made so the outside edge (long edge) are the measured length. The pieces need to be cut on the opposite fourty five degree angle to make the box. \___/ (like that!)
We only had to adjust it three times (the two different heights and the width that was the same for both the small and large rectangles). Also… can I just say how AMAZING it was to work in our new shop/garage?!
Once the pieces are all cut to size, time to get installing! I like to start with the end boxes in the wall corners, then fill in the middle boxes so I can get it exactly even. We started in one of the top corners, marking 5″ from the ceiling and from the wall.
Since we were going to be painting the entire wall a second coat, we just marked it in pencil. That mark was the outside edge of the corners. We used a level for straight lines (a laser level would be amazing for this! We used one on this moulding wall and we were able to get the entire room including the moulding wall assembled in one day).
In the video, you’ll see I line up the vertical pieces first. As I’ve installed this same type of moulding wall a few times now, I’d suggest marking the corners and a line across the top to mark the top edge instead.
You can install moulding walls with liquid nails (adhesive) or a nail gun. When you’re choosing the nail gun, you want to choose either a brad nailer or a pin nailer since they make much smaller holes to make it easier to fill holes.
I use a brad nailer to install my moulding walls. If you’re still building up your power tools, you can rent one of these or you can use liquid nails. The Ryobi kits with multiple tools and batteries are a great way to get started and often include a brad nailer- they go on sale around Father’s Day each year.
Once the top is marked, install the first piece of moulding (the top piece) using the brad nailer, taking care to make it level.
From here, add your side pieces, tacking the top corner with the brad nailer only. Make sure to get that mitred corner nice and tight and leave the bottom hanging loose.
Use your level again and tack your vertical pieces most of the way down the wall before installing the horizontal bottom of the box. I like to do it this way and finish nailing the bottom ends of the verticals after to make sure that corner can be nice and tight to avoid any corner gaps. Walls are not always straight and smooth and this helps account for some of that.
We did both of the outside upper rectangles before moving to the middle two. Then finished the wall off with the lower rectangles using the same method.
We did this so if our measurements were off at all, the spacing would still be perfectly equal. How do you double check?
Like I mentioned, walls aren’t totally square and straight so even though you measured the length of your wall when you did your initial math, I like to take this one step further to make sure my spacing is perfectly uniform between the boxes. Once your outer rectangles are up, get a precise measurement between them and subtract your rectangles (the two that still need to fit), then divide that number by 3. This will give you the measurements for the gaps between the rectangles. Ours was just a tiny bit over 5″ which allowed for our plugs in the wall.
How to Fill + Finish a Moulding Wall to Look Professional
When your box moulding wall is all installed… it’s time to get to finishing! This is the most time consuming part.
You’ll need caulk, a caulking gun, a damp rag, wood fill and a fine grit sand paper. And since you’ll get this stuff all over your hands… you should probably order some of this hand cream to slather on once you’re all done!
The caulk is for where the moulding meets the wall. Any grooves like this can be caulked to help the moulding blend seamlessly into the wall. The only time you DON’T want to do this is if you’re planning to remove the moulding wall and have used nails sparingly to allow that. Make sure to use a paintable caulk here. You can see one of my first ever YouTube Channel tutorials on how to apply caulk to trim here.
Just apply it using your caulking gun then wipe with a damp finger or rag to smooth out. I always use this paintable caulk and have for years!
Nail holes and the corners where your mitred cuts meet are best filled with wood filler (wood putty) and sanded lightly with a fine grit sand paper once dry. On moulding that’s not completely flat, I like to install this with my finger to follow the curves of the moulding. This way, there’s very little sanding that is needed.
Let the caulking and wood fill dry two hours before sanding/painting. Double check the instructions on your particular product incase it calls for a longer dry time.
Painting a moulding wall
I like to have my walls painted a base color before installing the moulding itself. Then, after the trim is installed, I give the trim itself a coat, then once that’s dry I do a second on the entire wall.
You can paint the moulding wall with just a paint brush and roller or you can spray it with a paint sprayer like we did in this green bedroom. In this room I used a matte finish instead of the typical eggshell finish and oohhhh you guys, it’s just so good!
The colour I chose is called Broadway from Behr and is the perfect deep black without feeling too overwhelming. I love this color. So much so that I wrote a whole blog post sharing about it- I’ve now used it in several projects, you can see it in all of them here!
I mentioned it in my design post, but when I was a teenager, I used black paint in my bedroom on my mouldings and it was such a deep, dark black and this is nothing like that… even though it’s black. I don’t know how to explain it.
see more about this perfect black paint color here.
The other thing that we did on this wall is switch out the brown swirled glass pendants for these modern black ones (discontinued). They are perfect on this wall and since they’re the only light in the room, I love that the exposed bulb allows the light to be so much brighter than the old ones. They’re also super affordable!
After this was photographed, we also switched out the light switch and plugs for black ones to blend in seamlessly with the wall. I love how that finishes the space off so beautifully!
I’ll leave it at that! If you have any questions about this moulding wall, I’ll do my best to answer them. It’s such a great project to add some visual interest to your room without adding more art to your walls. It’s really lovely texture and a moulding wall like this has been around for so long, it’s going to stand the test of time.
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Are you changing out you switch covers to black so they disappear?
I definitely thought about it but they are all hidden by the headboard and nightstand!
are your walls smooth or do they have texture at all? I am thinking of doing this but am worried the dark paint will make the texture on our wall more obvious
They are smooth! A matte paint will help hide the texture though if you love dark!
Did you use a gloss or matte finish ? What brand of paint ?
We used a Behr matte!
How do you have smooth walls? I’ve been wondering this for a while. Please explain this or direct me if you already have! Thank you!! Hopefully you see this
We do, yes! Most homes in our area do :)
I’m wondering this as well! I have my basement taped and sanded— they haven’t come back to texture— yet. Do I have the finishers do a different texture since I have the choice now being it’s new construction? You said Matte paint covers texture but it scares me for wall cleanups, it’s a recreational game room with kids so things will happen! Thank you for advice!!
We don’t do textured walls where I live! All drywall here is smooth, so I don’t have an opinion on matte with a texture! For a kids room, I do prefer satin or eggshell for cleanup though :)
Hey,
I am thinking of doing this. Can I put the moulding on then paint the entire wall and the moulding. Or is it best to paint the wall and then add the moulding and paint the moulding?
Yes totally you can! We had it painted prior, thinking we wouldn’t get to the moulding wall for quite some time!
Is this just a feature wall or did you do this on each wall?
We just did this on the headboard wall!
What is the length of your top boxes? I love this look and am hoping to recreate it on one wall in my dining room.
We’re actually moved out of there right now for flood restoration, but we measured from the top of the nightstands- I’d recommend doing this so you get the look you love customized to your furnishings!
hi there, would you mind sharing the measurements of the wall? I want to try to do this as a nursery feature wall but worried my wall is too small, its 86 inches wide X 93 inches tall.
I absolutely love this. I did a Kendall Charcoal board and batten on one wall and I am wanting to paint the rest of my living room the same color but wasn’t sure if that was too much wood. Wasn’t sure how it would look. From the looks of yours it looks great!
Love this! About how much were your materials….roughly! Trying to see if we can swing this!
Hi Barb, we can’t remember the total cost of this one. I just checked the link in the post and it’s $1.02 per foot, so it really depends how much you’ll need for your space.
Hi Colleen,
Love this simplistic yet classic look! It’s just what I’ve been looking for. One question, can you tell me the outside dimensions of your wall? Just trying to get some perspective. Our bedroom wall is 15 ft wide by 10 ft high.
Cheers
Shane
Awesome!!
I’ve been thinking of doing this on my wardrobe doors and most people told me that it needed to replace the doors completely. Your video is super helpful and the instructions are easy to follow. Thank you so so very for this amazing video. ??
Hello, what size (width and depth) doorstop moulding did you use?
Hi! Colleen has the trim she used linked in the post, it’s this one: https://www.homedepot.ca/product/alexandria-moulding-primed-fibreboard-stop-3-8-inch-x-1-1-4-inch-price-per-linear-foot-/1000118626
This turned out so cute! We are currently making a list of home projects we want to do for the summer here in Irmo & will have to add this to the list. Hopefully we can find time to do some painting too. Thanks so much for sharing!!!
I LOVE this and I think I’ll be doing it for my photography studio. Could you possibly provide the height and width of this wall. I have a few and I’m wondering which might work best for this look.
Hi Melissa, I’ve updated this post with more information- showing the same treatment on multiple walls. It will work great on any!