Billy Bookcases DIY

Built-in Billy bookcases are certainly not a new concept, but I never felt like the directions were close enough to what I needed. Enter my friend Kate. She gave some more details about the project, and I knew I was sold.

DIY Billy Bookcase

While I loved the 15” depth of Ikea’s newer bookcase, I knew I wanted them to go all the way to the ceiling. The extenders are only available on the 11” depth, so the decision was made for me. Whew! One less thing for me to ponder for hours.

BILLY Bookcase IKEA Adjustable shelves can be arranged according to your needs.


BILLY Height extension unit IKEA Using a height extension unit the wall surface is fully utilized while floor space is cleared.



After measuring the width of my wall, I knew I needed 4 bookcases. Once they were built and I had painted the backs of them, they were ready to be installed. It took some tweaking, tugging, scooting, and LOTS of measuring, but they came to about 2 1/4” apart—including the space to the wall.

Billy bookcase

We found these strips at Lowes that would be the width we needed. Two problems—the  grain in the wood (not my favorite) and they were pricey at $8.00 a piece. They had cheaper ones that were only 4 feet tall, but my husband argued that it would bother me having a seam half way up the bookcase. He was right, so we spent the money.

wood trim

Once these were attached with small nails and my nail gun, it really made the piece come to life. We have built-ins!

custom built-in bookcase

We didn’t put any wood underneath the shelves, but we did attach the shelves to the back wall with L-brackets from the top. I couldn’t get a picture of it, but we just used the brackets that came with the bookcases. It is covered by crown molding, so no one even knows.

DIY bookcase

Speaking of crown molding, that went up next. I basically got lucky. Crown molding doesn’t measure easily, so I guessed. I ended up with 5 1/4” crown, and it fit like. a. glove. Whew!

Benjamin Moore Boca Raton

That is where my luck ran out. Installing the crown molding? An absolute nightmare! Let’s just say the trim was too wide for my 10-inch miter saw, and every cut was nearly impossible to perfect. My FIL was such a trooper, and caulk has now become my best friend. It’s all good.

installing crown molding

Finally, we installed the baseboard. We carefully ripped out the old baseboard (since we didn’t have a little Dremel) and cut them down to size. We then re-mitered as needed and installed back in place. That wasn’t too bad.


The finishing touches involved caulk and paint. There were some seams where the baseboard went into place, and I wanted to fill in some minimal seams along the sides. Again, caulk and I got to know each other very well.


Sorry about the night shot, but this shows the caulking. Once it was painted over, it was seamless. Nice.


A couple of weekends of building and some late night caulking and painting…and she was done. Well, almost. Filling up an 8×12 foot wall of accessories and storage pieces is no easy task. I’ll be back in a couple of days to show her off with all her jewelry on!

Billy bookcase

Cost breakdown:

  • 4 Billy Bookshelves with 4 20” extenders= $280 ($300 with tax)
  • Crown Molding=  $15.00 (more if you want to do the whole room as we did)
  • Quart of paint (Benjamin Moore Boca Raton Blue)= $13.00
  • Trim pieces from Lowes 5x$8.00= $40

Total Cost= $368

**Update—If you’d like to see them all dressed up, here is the updated post.

Well, hello. Ahem. Allow myself to My name is Chris! And I’m a blogger! I got into blogging after spending months reading all the inspiration that is found in blogland. I thought to myself, “Self, I can do this. I might have something to offer too!” And so it began...

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