IKEA Library Wall Built-In Hack

Have you ever wanted a big and beautiful wall of built-in bookcases? It isn’t as hard as it looks! I used 4 IKEA Billy Bookcases and 4 IKEA Billy Height Extension Units. Since this is a custom design you will have to decide the correct number, width and height of the Billy Bookcases you are buying. There are taller Billy Bookcases and skinnier Billy Bookcases. The length of the wall minus the width of the combined bookcases was about 14″ and the 10′ ceiling height minus the height of the bookcases and extension units was about 21″ which left me with enough space to build a base, a rail support and an upper support allowing me to attach the upper trim and crown moulding.

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Supply List

• Billy Bookcases and Extension Units (optional, varies)
• 2×4 Lumber
• 2×6 Lumber
• 1×4 Primed MDF or Pine
• 1×6 Primed MDF or Pine
• 1×2 Primed MDF or Pine *optional: if you want to make the front edges of the shelves thicker
• 1×10 Pine (For the Rail Support)
• Crown Moulding
• Rolling Ladder Hardware Kit I bought one full set and two extensions. This will be dependent on your wall width
• 2.5″ Wood Screws
• 1.25′ Brad Nails
• 2.5″ Pocket Hole Screws
• Primer
• Paint
• Wood Filler
• Caulk
• Hardware for doors
• 1×3 Primed Pine, backer board for cabinet doors
• 16- Concealed Overlay Hinges

Tools Needed

• Miter Saw or Circular Saw
• Drill/Driver
• Nail Gun
• Measuring Tape
• Pencil
• Utility Knife
• Pry Bar
• Stud Finder
• Drip Free Caulk Gun I highly recommend you have a drip free caulk gun to save yourself a lot of headaches!
• Wood Glue

The first step to built-ins is to carefully remove the baseboard on the wall you are putting the baseboards on. If desired, you can reuse this baseboard for the front of the built-ins later. First, score the caulk with a utility knife, and then use pry bar at each stud location to lift the baseboard away from the wall. You will also have to remove a portion of baseboard from each of the side walls using a multi-tool. To determine at which point to cut, I added together the width of the base + the width of my MDF trim (.75″) + the width of my baseboard and then measured this distance from the built-in wall and cut the baseboard at that point.

Now I will build my base with 2×4 lumber. It should span the whole width of the wall and the same depth as the bookcases. The base of the bookcases is 11″. The actual width of a 2×4 is 1.5″, so I cut several pieces of 2×4 to 8″ (11″-3″). Since my wall is wider than 8′, I built my base in two sections and secured them both to the studs. Assemble the first base using two full 8′ 2×4 boards, using 2.5″ screws to attach the 8″ pieces to the 8′ pieces. Measure the remaining section and build a second base to size.

Assemble the Billy Bookcases and set them all on the base. Measure the remaining wall space to determine the size of your spacers. A 2 inch spacer between adjacent shelves works well since then a 1×4 MDF trim board will cover the gap and be flush with both edges of the shelves. After deciding on 2 inch spacers between adjacent shelves, I was left with 7 inches, therefore the spacers between each wall and end shelf needed to be 3.5 inches. Then I attached the 3.5″ end spacer blocks into studs using pocket hole screws. After determining the exact position of each shelf, make sure to cut out receptacles for any outlets or cable boxes.

Attach the shelves to the wall stud spacers and then attach the 2″ spacers between the shelves flush with the front of the bookshelves. If the end stud spacers are not flush with the front of the bookshelves, add a couple extra spacers that are flush with the front so you have something to attach the trim boards to.

At this point your shelves will be pretty secure as your end shelves are attached to spacers which are attached to studs, and the middle shelves are attached to the end shelves. I did add a couple L brackets between the middle shelves and the base. Now you will be building a duplicate of your 2×4 base, but this time out of 2×6 lumber for your ladder rail support. You could build this from 2×4 lumber as well depending on the amount height space. After you have built the 2×6 “base” put it on top of the bookshelves and secure it to studs. For extra sturdiness, you can screw each shelf through the top into the ladder rail support on top of it. The Billy Extension boxes do not come with a bottom piece, so you can either use one of the shelf pieces from your Billy Bookcases to create a bottom, or buy a 1×12 board to create bottoms for the extensions. Then you will mount all the extensions on top of the railing support and repeat the same spacer process. Then you will start the process of trimming the shelves. I added a 1×6 trim board to the bottom flush with the bottom of the shelves. You will notice that there is a small gap between the bottom shelf and the trim board since the shelves are slightly inset from the sides of the bookcase. This gap is easily filled with caulk or backer rod and caulk. Then you can reuse the trim board you took off the wall in the first step and nail it to the trim board. Then mount your 1×10 pine trim board by screwing it to the railing support. You want to use real wood, not MDF, for this trim board so it can hold the load of the railing and sliding ladder.

Next you will start adding trim boards to cover the gaps. A 1×4 board should cover the center gaps perfectly if you used a 2″ spacer. For the ends you will measure the gap and either rip down a board to cover the gap so it is flush with the edges of the shelves. The gap on my ends was 3.5″ plus the width of the shelf (.75″) equals 4.25″. I chose to use a 1×6 board without ripping it down, so it overhangs the side boards of the shelves, but you could do either. Your choice will affect the cabinet door size.

Now you will need to create a smaller support for on top of the extensions so you have a place to attach the top trim piece and crown moulding. You will have to not attach the second side of the support until after it is attached to studs otherwise you won’t be able to attach it to the studs. After it is attached, then attached the other second side of the support.

Attach the top trim board flush with the top shelf of the extension. Then you can add the vertical trim pieces like you did for the lower shelves. You then can attach the crown moulding to the top trim piece. Add the shelves, and if desired, glue and nail a 1×2 primed board to the front of each shelf to make each shelf look beefier and higher end. Now you will fill all nail holes and flush gaps with wood filler and caulk between the walls and shelves and between trim pieces that are not flush. You can also fill any extra peg holes in the shelves if you know you don’t want the shelves to be adjustable.

After the wood filler has dried, sand lightly until smooth, remove the dust with a wet rag and then it is time to prime the shelves. It is very important to prime IKEA furniture to ensure the paint will stick. After the primer is dry, you can paint. I highly recommend using a paint sprayer. If you don’t have paint sprayer, it may be easier to paint the shelves before starting installation. The paint color I used was Lick Paint Teal 03.

At this point you could be finished with the shelves, Yay! But I wanted to have the bottom closed off so I decided to add cabinet doors. I built my doors using 1×3 primed pine and 1/8″ backer board. Tutorial HERE! My middle set of doors were 15″x38″ using 1/2″ overlay hinges. My outside doors were 15 3/8″ x38″. After installing the doors using the overlay face frame hinges, I installed my favorite brass knobs using my Kreg hardware jig.

The last step is installing the ladder rail and extension according to manufacturer directions and then building a ladder (Tutorial Here!) and installing the ladder, which is very simple!

Now you have your very own library wall! Feel free to reach out to me with any questions! I am more than happy to answer any that you may have. DM me on Instagram or email me at [email protected].