1930’s Cased Opening Tutorial

Come see how easy it is to create the look of a 1930's cased opening!

Today I’m sharing how simple it is to create the look of a 1930’s cased opening!

If you’re trying to add character to your home, this 1930’s cased opening tutorial might be for you! With some basic materials and a few simple steps, you’ll see how easy it is to add dimension and beauty to what would otherwise go unnoticed. 

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We completed this project last year, and I’m finally getting around to sharing all the details! As you guys know, a lot of what you see in our home was DIY. But the previous owner did a lot of wonderful things in this home, too. One of the things they did was open up the entry into the living room. Yes..the opening in the photo above used to be a single doorway! Crazy, huh?

While I love how open and airy it is now, one thing that always bothered me was the drywall around the opening. Our home was built in the 1930’s, so the plain, drywalled cut-out almost felt too modern and not true to our home’s history. 

Here’s an older photo of what the opening looked like before –

cottage entryway

When we refinished the entryway with bead board last year, I asked my husband if we could finally create the look of a 1930’s cased opening. He agreed, and we used our existing window and the door trim for inspiration.

Here’s a close up shot of our french doors leading out to the sunroom –

1930's trim inspiration

This is the look we wanted to recreate! So let’s get started. Here are the supplies you’ll need for this project:

1930’s Cased Opening Tutorial – Supplies

1×4 pine or MDF boards

Corner trim (we used 3/4 inch)

Brad nails

Brad Nailer

Liquid Nails

Miter saw

Tape measure


Wood filler




Cased Opening Tutorial – Step 1

First, you’ll want to measure your opening to see roughly how many boards you’ll need. Be sure to purchase boards that are longer than what you’ll need. It’s always wise to leave room for error, plus you’ll be adding 1/4 inch in length to your vertical pieces, and roughly 7-8 inches to your top horizontal piece. But we’ll discuss that later on. 

Forgive me in advance for these cell phone pics of the process…not the best quality, I know.

1930's Cased Opening Tutorial Step 1 - measure!

For our opening we used 6, 6 foot 1×4’s (since we cased both sides of the opening).

In order to mimic the look of our original 1930’s trim, we chose pine 1×4’s. You could most definitely use MDF if you’d like, but we live in a very small town and pine is what’s most convenient for us. 

Cased Opening Tutorial – Step 2

It’s time to measure and cut your boards. This part can be a little tricky…in fact we started this project knowing what to do and somehow we still forgot and cut wrong. Measure twice, cut once! Ha! Will we ever learn?

Begin by cutting your vertical pieces first, and be sure to add a 1/4 of an inch in length to each! This is important! The reason for this is because you are going to offset all your 1×4’s a 1/4 of an inch away from your opening. This will give your opening a more finished, professional look without having to purchase any extra materials. 

If this seems confusing, refer to the photos below!

Cased Opening Tutorial – Step 3

After your vertical pieces are cut, it’s time to nail them to the wall. Use your tape measure and pencil to mark a 1/4 inch away from your opening in several places. 

1930's Cased Opening Tutorial Step 3 - measure and mark the wall!
Measure and mark the wall for your cased opening!

Once your board is lined up with all your marks, apply liquid nails to the backs of your boards, then nail them in place!

Cased Opening Step 3 - line up your boards
How to use pine boards for the look of a 1930's cased opening

Notice the 1/4 inch of drywall we left exposed? Once it’s all caulked and painted one color, you’ll see how beautiful it looks!

The easiest way to case an opening - 1930's cased opening tutorial

Cased Opening Tutorial – Step 4

Now that your vertical pieces are nailed in, you can measure for your top, horizontal piece. You’ll want to measure from end to end of each of the vertical 1×4’s you’ve just installed. 

Once your top board is cut, set it on top of your two vertical boards and nail it in place!

How to case an opening - step 4
Simple way to trim out a doorway! 1930's Cased Opening Tutorial

Cased Opening Tutorial – Step 5

You’ll notice we didn’t miter the edges. Let’s go back to my French doors…

1930's trim inspiration - 1930's cased opening tutorial

See how the top board sits directly onto the vertical? It really bothered my husband to do it this way, but I wanted our cased opening to look original and match the other trim throughout the house!

The final step is to add corner molding to each side of your 1x4s, and in this case we did miter each edge. 

Simple way to add cased moldings to doorways and openings!
How to trim an opening with pine boards easily! 1930's Cased Opening Tutorial

Cased Opening Tutorial – Step 6

Now it’s time for the finish work! This is where I come in.

Fill all of your nail holes with wood putty, and be sure to caulk every seam for a finished look.

How to trim an opening easily! 1930's Cased Opening Tutorial
How to trim out an opening - the finish work
Cased opening tutorial with pine

Once your wood filler and caulk is dry, it’s time for paint. 

I chose a special primer that is supposed to even block knot holes, but here we are a year later…and a few knot holes are showing through. For the most part, though, it’s working well. 

How to case an opening - 1930's Cased Opening Tutorial

We went with a classic white paint in order to match all of our existing trim. 

The simplest way to case an opening with trim! 1930's Cased Opening Tutorial

Finishing Thoughts

One thing you will notice is that we did not bring our trim all the way to the ground. You could most definitely tear out your baseboards or use an oscillating tool to remove part of them, we just chose not to. I don’t mind the way the baseboards wrap around the opening. 

And that’s it! Can you believe the before and after?? 

1930's Cased Opening Tutorial
The easy way to case an opening! 1930's Cased Opening Tutorial

What a difference! 

Cased opening diy tutorial
How to trim out an opening - 1930's Cased Opening Tutorial
1930's cased opening tutorial
How to trim out an opening - the easy way! 1930's Cased Opening Tutorial

I hope this 1930’s cased opening tutorial was a help to you! Did I miss anything? If so, let me know in the comments below! 


Come see how easy it is to create the look of a 1930's cased opening!


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  2. I’ve just stumbled upon your site. How beautiful; and inspiring to say the least! I would love to know the color and brand of your wall paint? Thank you so much for sharing your talents.


    1. Hi Melissa! So in that post the living room color is Halo by Benjamin Moore. 🙂 Thanks so much for following along!!

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  4. Hi,
    This is a great idea for a simple, yet good looking cased opening and I’ve decided to do it at our home using the same principles.
    Question from me – did you paint over the existing wall paint with a wood paint?
    Thanks in advance.

  5. I love this look so much! Is the interior of the cased opening still drywall but painted the same as the framing? Thank you!!

  6. Fell in love with this look and want to copy. Confused on the 3/4 corner trim. If you used 1×4, how does the corner trim stick out… did you pull it forward with a space behind it? Thanks for help

    1. It does stick out a bit because it is sitting on top of the 1/4, it’s not coming off the wall. I hope that makes sense? 🙂

      1. I love this…we are currently working on the same type of trim. I am curious if there was a bigger gap between corner trim and wall? We are running into that, did you caulk that gap? Thanks in advance!

        1. Yes there is a small gap, but you really can’t tell in my case it’s very subtle. If you can see it, you can use a wider corner trim. There is a wider and smaller version that should cover that gap. I hope this helps!

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