DIY Built-in Bookcase

When my wife and I first moved into our forever home we realized that we had a huge potential to do a built-in bookshelf. We perused many different websites to get inspiration and finally landed on a good one that fit our space.

After a little planning, budgeting, and the initiative to finally pull the trigger, we went to work on building up our office.

Cutting tools I.e. various saws
Nail gun
Measuring tools and levels
Drills/Drivers
Pry bar/hammer
Fasteners/nails
Sand paper of various grit
Paint/Stain (and all the stuff to go with those)
A friend to help lift heavy stuff (or act as your gopher, you know, “Go for this, go for that”)

Here is a video where I help explain our process.

After looking online at many different options of cabinets, bookshelves, and wood, in general, we finally landed on an idea from a popular pinning site. (Granted, this was before the pandemic reached quarantine level and wood prices were still low) We decided to purchase three cabinets from a local big box store and the associated lumber to do a two part build.

The first part would be constructing the support base, the cabinets & associated shelves, and the top shelf, or the main shelf (which we stained dark walnut). The second part would build the actual bookshelves themselves.

The space we were looking at is 16” D X 90” H X 120” W which would accommodate the three pre-built cabinets from the store and two small shelves in between those cabinets. Going into phase 2, I use 4’ x 8’ plywood to make cross cuts for the bookshelves. This will leave approximately 10 inches from the ceiling to install crown molding.

The way we budgeted (in terms of time and money) was this we landed on premade cabinets but build everything else i.e. the bookshelves. I knew that I wanted to reuse the trim from the original floorboards because they were in good condition but needed to be repainted. We wanted to put some fluting and crown molding for the bookshelves, once they were in. One thing that we went back-and-forth on was whether or not we wanted the bookshelf shelves to be adjustable. We figured that it was better to have them and not need them, than not have them and need them later especially once everything was already built & installed. So take that for what it’s worth.

Now on to the good part!

I built a base for the cabinets (which were 36" W X 30" H X 12" D, by the way) to sit on which were made out of 2x3s. They were deep enough based on where our closet was but not so deep to where the main shelf would overhang past the closet wall. The depth to where the closet would meet them adjacent wall was 16 inches. The depth of our premade cabinets was 12 inches and I knew that I wanted the main shelf to overhang the cabinets so I cut the 2x3s to make a 13 inch depth. 90” x 13” if you think about it in 2D.

After sanding, priming, and painting (and sanding/painting again) the cabinets, I mounted them onto the base and added a 1x3 support in the top recess of the cabinet. This was added to have something for the main shelf to “bite“ into but also to maintain support for the long-term. I also added spacers to both sides of the walls and drill those into the studs. This would add support for the outside cabinets but also to maintain a gap to add the trim later.

The main shelf was stained and cut to be 90” x 14” (Some overhang but not a lot, 1 inch). The main shelf was fastened from underneath, through the cabinet tops.

In my mind, the easy part was now done. Now, making it look nice and tidy took a lot more time & detail (and therefore, effort). Granted some people would think that the planning and making the cuts for the wood is the hard part and the detail is easy but this is just my opinion.

I had to cut some recesses into the cabinets in order to allow access to the electrical outlets. I also had to run our TV cable wire from the outside left section of the cabinet to allow that to travel to our antenna. Not a big deal, but something to keep in mind. I bought a wire way to hide it later from the super website with 2-day shipping. You know the one!

After sanding and painting the trim that I kept, it was time for reinstallation. This involves several tiny tiny cuts on the miter saw in order to get them to line up and fit just right. Especially the one where the baseboard needed a “lip“ to fit over the base that wasn’t removed. See pic 1 & 2

Tiny shelf supports were drilled, glued, and screwed in between the cabinets (after painting them as well). We found some woven baskets at the store that were also stained to match the main shelf. They were slightly too large and hung over the tiny shelves so we wound up using them in our side closet later.

Trim was added to the gaps between the walls where the supports for the cabinets were and everything was caulked in order to make a seamless look. Caulking also helps hide any screw holes, nail holes, or just gaps in general and looks great in my opinion!

I bought sheets of 4‘ x 8‘ Baltic Birch plywood to use for the bookshelves. I chose Baltic Birch to add more rigidity and the price (again, at the time) was only $5/each more expensive than pine ply. When I brought them home I ripped those down (with a circular saw) into 4‘ x 1‘ pieces for the frame as well as the adjustable shelves. This would leave a gap from the top of the frames to the ceiling, which was totally fine since we would be hiding it with crown mounding anyway. (Pic 1) I also used this opportunity (before screwing the frame together) to drill our adjustable shelf holes. For this I just bought a jig from the hardware store. I did not trust my own math, measuring, and drilling especially for the permanency of this shelf and the need for precision of repeatability! Now is the time for everybody’s favorite part sanding, priming, and painting........

I then brought everything into the office and dry fit to ensure everything was going according to plan. Similar to installing the pre-made cabinets, I had 2x3s screwed into the side wall studs and had spacers in between the bookshelves. Now everything could be drilled, glued, and screwed into the wall studs. I also connected each frame to each other via the spacers in between each frame. No going back now.

Once those were in place, I added a 1x4 to the top to have something for the crown molding to bite into and mainly to as act as trim. (Pic 2) Then the trim was added in between each frame to hide the exposed ply. (Pic 4) The shelf pins were installed and added to the frame and the shelves added. Then the trim for each shelf was nailed into place. (Pic 5) These trim pieces were all 1x2s, by the way.

After a sigh of relief, I took a much-needed break and prepped myself (mentally) for all the caulking, painting, and trim that needed to be added to finalize the top detail. All holes were caulked and repainted, as before. We added fluting to the sides this time which I thought was a nice touch. (Pic 1) the crown moulding was then sanded, primed, painted, and installed with a nail gun. I definitely needed my wife’s help for installing this piece.

Now it was time to start populating the bookshelves!

Once all of our books were on the shelves, we bought book ends to keep them in place and some antique library label holders. This helped for maintaining space for all of our knickknacks and knowing what style book was where i.e. fiction, non-fiction, anthology, etc.

We finally have a place for all of our books to rest nicely, as opposed to boxes/stacks on the floor! I also like that my wife maintained space to put our cool collectibles. (PS if you like that skeleton key cloche in picture 2, I have an instructable about it)

And that’s that.

This project took us several months of planning and execution. All in all, I thought it was a daunting task and a big commitment, but once we got into it, it WAS time consuming but relatively simple. Just build big boxes and seal it up after painting. No big deal…right?!

Once we got the bookshelf built, we got a new desk & office chair, as well as a nice carpet. That carpet really brings the room together!

Thanks for looking and let me know what you think and whether or not you attempt a task like this! If you would like more detail for a certain step, I will try and get back to you in a timely manner. Just comment, as well!

PS You could just stop at phase 1 if that’s your plan! And it would be cheaper.
Looking at prebuilt bookshelves, even cheap ones, you may be looking at the same price if not more after all the hardware and trim to gain that seemless & finished look. Just something to keep in mind for planning. Trust me, we thought about that, too. We rather would have a sturdy long-term build. Plus, I like getting my hands dirty!