Heang’s Office, Part 3 of 4: DIY Built-in Bookcase

Welcome to part 3 of Heang’s office! This is the part of the room I have been most excited to share with you. This DIY Built-in bookcase took me a long time to install, but it was totally worth it. Heang’s office needed something stately and special to shift the feel from a casual den to an office fit for a businesswoman.

It wasn’t just about adding more furniture. It was about creating a unique piece that would feel impressive and important. This project took a plain blank wall and gave it a sense of purpose and sophistication. And the best part is, it’s simple and affordable.

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Installing the Bookshelves

I started this project with an Ikea system. If you’re considering a DIY Built-in Bookcase project like this (and you are not already a cabinet maker), I highly recommend starting with something prefabricated. I really enjoy working with Ikea products, and for this project, I chose to use the Ikea Billy line of products.

The first step in the project is to assemble the bookcases. Thankfully, Ikea products are pretty simple to put together, so building these five bookcases didn’t take much time at all. You’ll notice in the photo below that I used my Ryobi multitool to notch out the back of each bookcase so that it would fit flush against the wall without needing to remove any baseboard. This is a very simple step that helps the DIY built-in bookcase look more custom.

Beauty Takes Time

Once all the pieces were assembled and placed in the room, I could immediately see the vision coming to life. This is a great lesson for any new DIYer. Sometimes you have to trust your gut and keep moving forward even if things look a little chaotic at first.

Another great way to envision the future of your project is to tidy up your tools and supplies so you can see your project coming to life without having to squint to ignore the dust! Plus, it’s much less frustrating to work in a tidy space where everything is within reach and there’s less risk of making mistakes.

Adding the Trim

Once the bookshelves were in, it was time to start adding trim. Trim creates a finished look, giving the illusion of a custom, built-in unit. For this project, I created this beautiful arched trim that elevates what started as basic cabinets into something intentional and architectural.

Here are the steps for creating the arch:

• Decide how wide you want the base of the arch to be. Measure that distance on your board and then mark the center point.
• Measure a piece of twine (ribbon, yard, or thin rope will do) that is half the length of the widest part on the bottom of your arch.
• Affix one end of your twine at the center point of the base of your arch. You could use tape, glue, or a nail. Preferably something that doesn’t leave residue or damage the wood.
• Tape a pencil to the other end of the twine.
• Extend the pencil until it is taut and begin to move the pencil in a large circle around your center point.
• Stop when the pencil has gone 180 degrees around to the opposite side of the board.
• Once you’ve drawn your arch, use a jigsaw to cut it out. Then sand down the edges until smooth.

If you’d rather purchase a tool than do this part by hand, you can buy a compass scribe on Amazon for a great price. Full transparency: I have not used this tool, but it looks like an easy way to get this job done.

Once I had all three arches cut out, I installed them using my brad nailer and some support brackets that attached them back to the wall.

Notice the left and right panels at the top of the arched section. I cut a channel out of the existing crown molding on each side to allow the plywood to fit snugly against the wall. I used my multitool for this step, and it was fairly easy to do.

Then, I added trim to the faces of the cabinets to give the illusion that this is one large piece of furniture rather than five separate pieces. Once all the trim was installed, I caulked all the seams. This step is essential in creating a professional-looking built-in.

Finishing Touches

Take a look at the beauty! A couple of coats of paint completely transformed this piece. But before we get to painting, here are some important tips about painting Ikea cabinets:

• Once you have installed the shelves, take some wood filler and fill in all the extra little holes on the inside of the bookcase. Those little holes are a dead giveaway for furniture assembled at home. Once you paint over them, no one will ever notice they were there.
• Before you paint Ikea furniture, you need to prime it. I recommend Zinsser B-I-N primer. If you paint this furniture without primer first, the paint will peel right off.
• Caulk the fold lines on the back board of your Ikea bookshelves. This makes them sturdier, so you’re less likely to see the crease.

After priming everything, I added two coats of paint, installed this gorgeous gold hardware, and voila!

Styling the Bookshelves

There are so many different ways to style your DIY built-in bookcase. The most important factor is that you like it. That said, here are some tips to help you elevate your shelves.

Balance and Symmetry: Arrange items with a sense of visual balance—this doesn’t mean everything has to match, but distributing weight and color evenly helps the space feel cohesive.

Layering: Mix heights, shapes, and textures by layering items like books, art, and objects. You can even place smaller pieces in front of or on top of larger ones for depth.

Negative Space: Don’t fill every inch. Leaving some empty space prevents the shelves from looking overcrowded.

Personal Touches: To make the space feel authentic and lived-in, include meaningful items like framed photos, heirlooms, or favorite books. We also achieve this by purchasing second-hand items like antique books, crystal bowls, brass candlesticks, and baskets.

The purpose of styling is to make a space feel more like your own, so lean into your interests and choose items that feel special to you.

Beautiful and Functional

I am so proud of how this project turned out. I really stretched my skills and tried things I’d never done before, and I’m happy to say that Heang is thrilled with it.

This DIY built-in bookcase adds both function and beauty, helping to create a space that feels organized and inspiring. It offers a place for everything and is visually appealing. I can’t think of a better view to see from her statement-making, glass-top desk!

Now It’s Your Turn

DIYing your home is one of the best ways to make your space feel truly your own without spending a fortune. Whether you’re painting a room, building shelves, or repurposing thrifted furniture, each project adds a personal touch that reflects your style and creativity. DIY allows you to customize your home in ways that store-bought items often can’t, and the sense of pride that comes from completing something with your own two hands is unmatched.

So, now it’s your turn. I know you can do it. And when you do send me a picture.