Ikea Built In Hack with Billy Bookcases

This is the ultimate Ikea built in hack: use Billy Bookcases to install a DIY entertainment center! Inexpensive solution for a playroom, bedroom, or office. See full process, from plans to installing crown molding/baseboards.

From the time we moved into this home (one year ago last week!), I knew that we were going to have to do something about the storage in the playroom. It's on the smaller side (one of my regrets...I wish we had made this space bigger), so finding useful storage space can be a little bit of a challenge.

I absolutely love the look of built in cabinets - obviously, since we have them in several other places in the house. We have a larger wall with a TV mount in the middle that I knew would be a perfect place for some built in storage and an entertainment center for the kids.

After a few weekends of work, we were able to convert this mostly unusable space into a set of built-in cabinets that turned out better than I could have ever imagined! I am in love with the result of this Ikea built in hack - I think it absolutely frames the room and, in addition to being beautiful, gave us some much needed storage space. Here's how we put it all together...

(Affiliate links used in this post. Read more about my affiliate link usage here.)

Ikea Built In Hack with Billy Bookcases: Step-by-Step Process

1. Measure your space and plan, plan, plan.

This is the simple little graphic I put together when we were planning this space. The two taller side Billy bookcases are 31.5x79.5" and the one in the middle is 31.5x41.5", so I was easily able to fit them into the wall by measuring the total width of the wall and plotting everything out. We had to put our bookcases a couple of inches apart to give us enough room to see and maneuver our flat screen TV...you might not have to worry about that, but if you're using the layout we did and have a TV that's 26" or more, you'll definitely need to consider this. It's easy to cover those gaps if needed though - more on that in a minute.

In addition to your bookcases, you'll need...

• a good drill (for building shelves and securing brackets to the wall)
• a miter saw
• small white finishing nails
• a nail punch (more on that later)
• at least 8' of crown molding - we used 3.265". Plan on making a few mistakes cutting this!
• Depending on whether or not you can reuse your baseboards if removing from the wall, enough baseboard to cover the entire front and sides of the shelves
• Caulk
• Wood Filler
• Sandpaper
• Particle Board
• 1" Chair Rail Moulding
• Semi-Gloss or Gloss White Paint

2. Build your bookcases.

This process is pretty straight-forward - I mean, who hasn't had to build cheap furniture at one time or another, right? The Billy bookcases are no different - really simple to put together.

I will give one quick suggestion - when you're building, mark the location of the middle shelf on the back of your bookcase (before you put the solid white panel in). You'll need to nail this panel into place to secure it, and by marking the level of your shelf, you ensure you'll get your nails into that middle shelf and that they won't be exposed above or below it. We learned this one the hard way.

Then, one of the fun parts - position your shelves on the wall!

At this point, you can see whether your base molding will fit into these handy dandy little cut-outs Ikea puts in the Billy bookcases. If it does, lucky you - you can skip the next step! Ours obviously doesn't.

3. Remove base molding if needed.

If your molding didn't fit in the bottom notch, move shelves and very, very carefully pry your base molding off of the wall. We were able to reuse this molding on the front of the shelves because it didn't break when we removed it.

You'll probably need to remove nails from the wall before moving on too - we had a ton sticking out.

4. Secure bookcases to the wall.

Ikea's Billy Bookcases come with bracketing hardware to attach your bookcases to the wall. Just make sure these are screwed into a stud to make them extra secure. It doesn't matter if the brackets are showing like this - you'll use crown molding later to cover these up.

We secured the center bookshelf with brackets like this. We knew we would be covering up the top of this with a piece of MDF, so it didn't matter what it looked like at this point.

5. Attach crown and base molding.

I'll admit - I hate. working. with. crown. molding. It is such a pain to cut. I just don't have the mind to think about multiple angles and cuts at once.

But, if you have a miter saw (which is kind of a must for this part), position your crown molding upside down...there should be a flat part on the back of the molding that you can place on the vertical bar of the saw to kind of help you with the cut. This is the part that will eventually be connected to the shelves.

Once your molding is positioned the right way on the saw, you'll cut 45 degree angles for each corner. You *should* need the pieces on the sides of the shelves to be a smidge over 11" from the flat part that touches the wall to the inside of the 45 degree angle...but definitely measure this, as it varies a little from shelf to shelf and you need it to be pretty much perfect. The piece on the front should be around 31.5" from inside of the angle to inside of the angle at the other end - but again, it varied a little bit on ours, so measure a few times to make sure it's right!

Once it's cut, use a little bit of wood glue at the angles and pieces that touch the shelves to help hold the molding in place and nail 1-2 times at the ends of each piece. This is something we didn't do until the end that should have been done on this step: use a nail punch to drive the nails in past the surface of the molding so they'll be easier to patch later. As you see above, the molding doesn't have to be pretty at this point - we'll clean it up later on!

The base molding was much easier to cut - just simple 45 degree angles on the miter saw. We were able to reuse the piece for the front from the original baseboards on the wall...we just had to buy one piece to cut into the two side pieces (and, if you look really closely, it doesn't match perfectly - not that that drives me crazy or anything 😉).

Again, a little bit of wood glue on the angles and whatever will be touching the bookcases helps to hold it in place, then just use a nail every foot or so (punching the nail in past the surface of the board after it's secure).

6. Attach middle shelf and cover gaps.

We cut a piece of particle board to cover the entire top of the middle shelf and the gaps between each shelf, so you wouldn't see the gaps from the top and it will look like one continuous shelf. We glued this to the top of the middle shelf with some E6000 and secured it a little bit more by adding 4 screws from the bottom. Just make sure these screws are longer than the thickness of the top of the middle shelf but not as long as the top of the middle shelf plus the particle board...you don't want them coming through the top! I think we used 1.5" screws for this.

To cover the front gaps, we used simple poplar board - this was one 8 foot piece of ⅜" x 3" board cut to fit each gap. The ⅜" thickness lined up perfectly with the top of our baseboards. We simply nailed the poplar in place (again, punching the nails in so they can be patched).

We also cut teeny tiny squares to cover the outside edges of our particle board - it just didn't look right without this little detail. You could try to notch out one big piece of particle board so there are no breaks, but we aren't that skilled. 😂  We just glued these little pieces into place and caulked them really well in the next step, and you can't really tell that it isn't one big piece unless you look closely! Then, we used this 1" chair rail molding around the front to coordinate the front piece with the rest of the molding.

7. Caulk and patch.

This is the most important part to making this look like one big, built-in piece!

First, you're going to go over each nail hole with wood filler. Just kind of smear it in with your finger - no tools required. Once this is dry, go back and give it a good sand so the surface is smooth all across.

Next, I went around every edge of the cabinets that touched the wall and caulked any gaps. I use this caulk (as I have for many other projects) and it's so easy to work with. I wasn't great about taking pictures of this step, but I showed how I caulk things like this in my plantation shutter install post.

I also used this caulk on all of the gaps in the molding, smoothing it out with my finger as I went. It's especially helpful to use a wet paper towel to really wipe off any excess as you go. (See, doesn't that look so much better than the last time I showed it? The caulk makes a world of difference!)

8. Paint molding.

(Picture courtesy of the best 6-year-old photographer I know.)

The last step is (somewhat) easy! All you have to do is go over the whole thing with a coat of white paint.

The hard part is actually finding white paint. For a year, I've thought our trim throughout the house was Sherwin Williams Snowbound - there is even a huge leftover container of this color left in our garage. I tried painting our trim with this color, thinking it would be the perfect way to blend our existing trim on the wall into the trim on the built-ins.

Nope.

It was SO much darker than the cabinets and existing trim. I have absolutely no idea where they used this color in our house! So, after a heavy second and third coat of (actual) white paint, it was fixed. Just be warned - just because you *think* your trim is white and that color will work on this, it might not - you need actual, 100% white. I'd also recommend either a semi gloss or a full gloss to match the finish of the cabinets.

I absolutely can't believe how pleased I am with this project! It wasn't all that expensive (under $300) and totally made over our playroom. It offers functional and pretty storage and really gives the space a focal piece.

On Thursday, I'll be back to show off the rest of our playroom and talk about how we organized these shelves, along with the rest of the space! (Update: that post is now live here.)