Heyo, folks! Most of the time, my projects are spontaneous and I decide to tackle them not long after I see the inspiration. However, that is not my husband’s approach. I wanted learn how to do wall moulding in our down stairs living room.
Knowing my life would be a lot easier if I came up with a plan first, I asked him to help me come up with one. Here’s how he helped me to box trim molding to the living room.
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Planning Out the Placement of the Molding
There are many different steps that go into planning how to add box molding to a wall. My husband and I used a Cad program to design the layout for the boxes. This way we had exact measurements and knew exactly how much wood to buy. Waste not, want not. (Name that movie).
First-Take measurements of everything in the room that is an cannot be moved (fireplace and sconces in my case) or a decoration that you want to incorporate (such as a picture or mirror on the wall).
Second-Layout. There are different options such as stacked boxes, floor to ceiling boxes, stacked boxes separated by a chair rail. Determine the layout you want.
I am doing stacked box molding on the wall to soften the immovable objects in the room. Instead of trying to help hide them, I’ll use the boxes to make them look intentional.
Third-Once layout is decided, next thing to consider is measurements. How large the boxes will be, how far away from the edges of the wall, ceiling, floor, etc. A tip is to make all the distances (from the floor, ceiling, in between boxes, from chair rail, etc) the same length.
Lastly-Style. You can learn how to do wall moulding with almost any type of trim. (I ended up using some trim I found on facebook marketplace to save money). I wanted something simple and that looked like it could have been there for 100 plus years.
Gather Supplies to Add Box Wall Moulding
Here is a list of tools I used when installing the box molding on the wall. There may be some additional things needed, but these items will get you started!
- miter saw (or miter shears, miter box)
- molding of your choice
- nail gun
- finishing nails
- measuring tape
- caulk gun
- laser level (be smarter than me and use one)
- spacing block-a spare piece of wood
- wood filler
- chair rail if your design has it
Prepare for Box Molding Installation
Take Dimensions of Everything
The dimensions of my wall are 178 inches in length from edge to edge and 108 inches high from floor to ceiling. Subtracting the baseboards from the bottom (a 1×6 so really 5 1/2 and the crown molding), the height of all the walls is 99 inches.
The next question to ask is how many boxes will fit and look good in the space. Reminder: I don’t just have a blank wall, I have to contend with the immovable objects in the room.
On this wall specifically, I have a fireplace and sconces. There will also be art above the fireplace so this is a another factor to consider.
I am a visual learner so I made a mockup in Canva so I could get an idea of the layout I wanted and how many boxes would look good. Canva is great for beginners to make models, but in a cad program or sketch up, you will able to use exact measurements.
How Many Boxes?
The plan is to do two sets of stacked boxes on each side of the fireplace separated by a chair rail. I needed to determine the heights of the wall above and below the chair rail. To do this I just measured under the chair rail (35 in) and subtracted that from 99 and also accounted for the width of chair rail.
No matter the dimension of your wall, how many boxes, or any other accommodations, the key to a cohesive and professional look is to have even spacing! Let me say it again, EVEN SPACING!
We are doing 6 in spacing for around all the boxes. This includes from the crown molding, edges of both walls, chair railing, and the baseboard. The only place where it is slightly more than 6 inches are on the bottom boxes that sit beside the area below the mantle.
Calculate the Width and Height of the Boxes
Next, we calculate the height and width of the all the boxes. Let’s start of the width. Unfortunately we have do some math, but simple math.
Start with the width of the wall (178 inches) and subtract your space in between the boxes (6 inches) so (6×4)=24. 178-24=154.
Divide that by the number of boxes (for me that’s 3). 154/3=51.3 (I’m rounding down to 51) is the width of the boxes. The width of the boxes below the chair rail will be the same width for a sense of cohesion.
Now for the height. Much the same formula, height of the wall and subtract the spaces between the boxes. Use this formula for make a standard floor to ceiling box or stacked boxes across a blank wall.
For me, the two boxes above the chair rail are the same height and width. To calculate this, I took the height of my wall which is 99 inches.
Now I take that height and subtract the top space from the ceiling (6 in) and the chair rail (6 in) to find the height. 62 1/2-12=50 1/2 inches. Next I take that height of below the chair rail and subtract the spacing above and below (6+6=12). 35-12=23 inches.
TIME TO GET BULK CUTTING!
Time to Make Bulk Cuts
Since some of my boxes are the same width and height, I can make a series of bulk cuts. The widths are all the same, so I can make 6 cuts.
Pro Tip: Making a diagram of your measurements shows the exact amount of wood trim needed, but always buy extra in case of mistakes. Cut all the trim pieces at once for accuracy and quick install.
My measurements listed above are from outside corner to outside corner. To make the same measurements precisely and without having to remeasure every time, I create a stop block. A stop block is a jig that assures the same measurement be cut accurately over and over.
This is the decorative trim I used. To make these box moldings, the trim is cut on a 45 degree angle. You can make these with a miter saw, miter box or even miter shears. The decorative lower edge is the inner seam of the picture frame box and the higher edge is outer seam.
This is usually the case, but I did the opposite. It’s really up to you. Either way, it will look good, but that is typically the way you do it.
When making cuts, the cuts should all be made inward towards what will form the inside portion of the box frame. To do this, you’ll have to move the saw blade to 45 degrees to the right and the left.
Now we are ready for assembling the boxes on the wall!
How to Install Box Moulding On The Wall and Tools Needed
Now that we all of trim pieces cut, we can install it on the wall. Most of the tools we discussed are for the planning and preparation of the wall moulding. Here are three tools that are essential when installing the picture frame molding to the wall:
- laser level
- tripod for laser level
- space block
- nail gun
- nails (I used 1.5 in)
- regular level (this is what I used)
First, set up the laser level if you have one, if not you can measure and level by hand. Use the space block to measure and test the distance from the wall.
We are going to start with the far end of the wall on the left side. Place the space block against the edge of the wall and mark with a pencil. Aim the laser level to match up with that line or make a mark and draw a line with a hand level.
Place the vertical trim piece right next to the space block and check the levelness against the laser level. Add a nail in the middle to secure the board to the wall, but not all the way. Work in an L, one vertical and one horizontal piece so you can adjust the pieces as needed to match the angles together.
Only add the remaining nails after ensuring the trim boards are level.
Here’s a secret, I never find studs or worry about hitting them. I do angle my nails before placing in the box moulding to ensure it is not easy to pull off.
The steps are the same for the remaining boxes. Keep going along the whole wall. Remember to keep using the space block to get that even spacing where necessary.
Once all the walls are done and we have learned how to do the wall moulding, let’s talk about how to finish the details to make it look super professional.
- Caulk every edge along the inside and outside of each box molding with paintable acrylic sealant
- Fill the nail holes in the trim with spackle or wood filler.
- Sand those filled holes smooth once it has had time to dry
Pro Tip: Give some thought to sheen. I painted the whole wall, crown to baseboards in the same color. Eggshell is my preferred choice for walls. For the crown, baseboards, and molding I used a semi-gloss finish. The different sheens in the same color add a level of professionalism and custom look to the project.
FAQ on How to Do Wall Moulding
What type of trim should be used?
This is really down to personal preference. I’ll link the one I used again here. Any kind of decorative trim can be used. I like a more traditional look, but you can change it based on your own style.
Can you paint the box molding a different color than the wall or should it be the same? Sheen?
I’ve kind of already answered the sheen question. I think a different sheen on the trim boxes and the walls looks intentional and professional.
You can also do a different color on the wall moulding or even leave the wood natural. If painting, Whatever color I would would choose a semi gloss or high gloss sheen on the wall molding and eggshell or satin on the walls.
Accent wall or whole room?
Should the wall molding boxes be on one wall or a whole room, well this again comes down to personal preference and pocket book most likely. It is more expensive, but I think it give a more complete and professional transformation.
I suggest if you want to add molding to an enclosed room, save up to be able to add box molding to all the walls. In a more open space such as a entryway, foyer, open concept living space, etc. one wall would work just fine which is what I did.
Well, that’s it. Now you know how to do wall moulding in your home. Whether you do add box moldings on a wall or across a whole room, it’s sure to add some character. I love how such a subtle feature can make such a difference and add so much charm to a room.
My favorite part is how far back in history you can see this similar type of design in houses dating back centuries. It elevates the space while making it look like they knew how to do wall molding 100 years ago. So tell me, would you try this in your home?