Several years ago we turned a blank wall in our home into a wall of built-ins using IKEA Billy Bookcases. I published a blog post tutorial for our IKEA Billy Bookcases turned wall of built-ins in October of 2020, and I have been answering questions ever since. I never mind answering questions at all, but I thought it would be helpful for people embarking on this build to have another blog post to refer to for questions. So that’s the why behind this IKEA Billy Bookcase Hack: The Most Frequently Asked Questions blog post!
If you don’t find your question answered in the original post or below, you can message me on Instagram, or leave a comment below!
Before we get started, I must mention that this is just a roundup of frequently asked questions. If you want the entire IKEA Billy Bookcase tutorial, you will want to read the original blog post, which can be found here: IKEA Billy Bookcase Hack – Wall Of Built-ins
IKEA Billy Bookcase Hack: The Most Frequently Asked Questions:

1. Are the lights hardwired?

Yes, the lights are hardwired. My husband is an electrician, so he wired them. You can see in the above photo, the wiring he left out on the top right before we did anything else. If you are hardwiring lights, you will want to have an electrician come do his/her part before you start the project.
That being said, you definitely do not need to have lights hardwired. I have seen plenty of great “hacks” you can use if you don’t want to wire in lights. Check out this post by Nesting With Grace for her “magic light trick.”
P.S. Where are the lights from is another question I get daily! Find the Brass Wall Sconces Here.
2. Where did you get the doors?

The doors are from IKEA. They are the Oxberg Doors. We used these knobs on the doors.
3. Did you have to do anything different with the door hinges?
Yes, we did have to adjust the hinges for the trim.
We drilled in to the cabinet just as you would do if they were regular Billy Bookcases. We just adjusted for the thickness of the wood trim we added. For instance, if you add a 5/8″ piece of wood, you will move the hinges out 5/8″. We adjusted for the extra depth, and used the screws they gave us to drill into the cabinet in a different spot. However thick the wood is on the front, you will move it that amount.
4. Did you paint the bookshelves?

We only painted a small portion of the actual Billy Bookcases. (We obviously painted all of the trim work we installed.)
You can see from the photo above the portions of the actual bookshelves we painted.
We painted only the top of the 1st bookshelf, the inside of each shelf, but only on the left and right (where we attached molding and filled the shelf holes,) and the top. The rest we left unpainted. We used a Zinsser primer before painting the bookshelves.
I have seen IKEA hacks done where the whole bookshelf is painted, and it looks amazing. I wanted ours to be white, which worked out to be the easier route, because we didn’t have to paint everything. If you are wanting to paint yours, check out this blog post by Chris Loves Julia.
5. What color did you paint the Billy Bookshelves?

We used Benjamin Moore Simply White in an eggshell finish to paint the portions of the Billy Bookcases that we painted. (See #4 above for which portion was painted.)
6. What color are your walls in this room?

Our walls are Benjamin Moore Simply White, which is the same color as the portion of the bookshelves that were painted. (see #4,5 above for details on this.)
7. How did you cut out for the bookshelf electrical?

We used a jigsaw to cut out a portion of the bookshelf for the electrical plugs.
Note, we have received the following question a couple of times regarding the electrical boxes: “Did you keep them mounted as they originally were to the stud, or remount them to account for the thickness of the back of the shelves?” Answer, my husband used box extensions and longer screws.
8. What did you build the IKEA hack base with?

We built the base for the bookshelves to sit on with a mix of 2x4s and plywood.
9. How did you attach the trim to the wall and ceiling?

We attached trim pieces to the walls and ceiling, so we would have something solid to attach the bookshelves to. We used screws into the portions where we could hit wood, and sheetrock anchors on the rest.
10. Did you use the backing that comes with the Billy Bookcases?

We did use the backing that comes with the Billy Bookcases. We have had zero issues with it, and I think it still looks great years later.
11. What did you use to fill the pre-drilled holes?

Shown above, IKEA Billy Bookshelves come with pre-drilled holes for shelves. This is so the shelves can be adjustable, which is great! We opted to fill those holes after deciding on shelf placement. I have seen others that haven’t, so this is completely a matter of preference.
When filling these holes, we used DAP DryDex.
12. What is the size of your wall?

The blank wall was 141″ wide, and our ceilings are 9′ tall.
13. How long did the process take?
We did the building of it all over the course of 2 days, and then took our time over the next two weeks for caulking, filling holes, sanding and painting.
I took my time filling holes, sanding, filling again, sanding again, etc. I did not want it to be noticeable where the holes were at.
14. What tools do I need?
Here are the tools that we used for the project:
- air compressor with brad nailer
- compound miter saw or this one
- table saw or this one
- jigsaw or this one
- drill
- And if you aren’t handy, and a handy husband, wife or friend will help 🙂
15. How much did it cost?
We didn’t keep a record of the exact prices, and the cost will vary depending on how big of a bookshelf, doors/no doors, etc., but this should give you a ballpark idea:
- (4) IKEA Billy Bookshelves $200
- (4) IKEA Billy Bookshelf height extenders $100
- (8) IKEA Oxberg Doors $280
- paint, caulking, hole filler, etc. $125
- wood- molding, trim pieces, material for base, etc. $200
- hardware- we used these knobs $100
- estimated cost = $1,000
A few additional notes:
The molding that we used: 1×10 MDF trim for top; 1×6 MDF trim for sides; 1×4 MDF trim for between each shelf; 2x4s & OSB crown molding for top.
I have an IKEA Hack highlight on my Instagram page that you may find helpful. I have included videos and more details that are hard to convey in a blog post. You can find that highlight here.
I hope you found this IKEA Billy Bookcase Hack: The Most Frequently Asked Questions blog post to be helpful! Let me know in the comments below if you have anything additional to ask!
If you are wanting to know where something pictured above, you can shop my home here.
Other posts you may be interested in:
8 Items To Use For Simple Shelf Styling
How To Decorate Shelves & Bookcases: 7 Simple Steps
IKEA Billy Bookcase Hack – Wall Of Built-ins
Hi! I’m doing this hack in my living room right now and i have just one tiny question!
Witch distance do you have between the shelve? Thank you!
Hi there. Ours is 3.5″, but can be different depending on the span of your wall.
Hi we are working on starting this in our home to thank you for the great write up one question it looks like in one picture without the doors on that the shelf that would meet the top of the doors is inset a little did you have to add something to bring the shelf further forward especially after adding the trim seems like the would be a gap between the two of the door and the shelf.
Hi Brian. I have an IKEA Hack highlight on my Instagram Page that will answer this. It is better answered with video, so I explained it there.
https://www.instagram.com/thesommerhome/
Hi,
I want to do this in my hallway entry since it’s long and next to my living room yet the walk I want to do this on does not have walls to the left nor to the right of it. How essential is it to put wood trim on the walls ? Would putting it on the ceiling be suffice?
I’m not sure. This would be a question for IKEA. I wouldn’t be able to answer this.
Hi! I am in the process of completing this hack in my husband’s office. For the vertical MDF trim between bookcases, did you nail the MDF directly into the billy bookcase? Or did you just use glue? Or was there a piece of trim (like what you did along the ceiling and walls) to mount the MDF to? That is the only part I haven’t quite figured out yet. Thanks!!
Hi Jill. I apologize, but I am just now seeing this comment! We nailed the MDF trim to the bookcases.
Hi! Is there a reason why you bought the Billy bookcase and doors separate even though there is a Billy bookcase with doors already attached for sale? Same questions for the extension piece since they sell a Billy bookcase that is 93 inches. I am in the planning phase of this project and I am just trying to figure out what pieces I need to order.
When we did the project that is the only way you could purchase them.
How many coats of Simply White paint did you use? I did the same thing and I have one coat of primer and one of Simply White and I’m afraid I may need a second of SW. Did you paint two of SW?
Thanks.
Yes, two coats.
Hi there… Great information!
Just wondering – do you happen to know the depth between the back of the bookcase uprights and the rear of the back board when it slides in – I’m assuming it’s about 1 cm?
Asking because of the way I need to baton these a little way away from a wall – needing to attach a bar across the top and the middle fixed shelf- and need to know the recess to allow for…
Asking now as don’t have the bookcases yet (they are on order) but want to get ahead with materials and prep!
Thank you.
Glyn
Hi Glyn. I apologize, but I am not understanding what you are asking. I had my husband read your question as well (he is the one who did the DIY,) and he isn’t understanding what you are asking either.
Beautiful work, looks amazing!
A (maybe dumb) question – was this any easier than just building the whole shelving system yourself?
Given the amount of work put into “building in” the Billys, it SEEMS like it may have been easier/cheaper/sturdier to also build the verticals and shelves – am I missing something?
Thank you so much for posting and your guidance.
We are the furthest thing from a family of carpenters and didn’t want to have to add figure out how to build shelves and doors to this DIY.
What did you use to attach the bookshelves to the platform?
With L brackets. Photo of it in blog post. https://thesommerhome.com/billy-bookcase-hack-tutorial/
Looks great. What is the thickness of the trim you used?
Do you find the lighting is ok since they’re positioned in between each bookshelf instead of over each one?
Lighting is great for us. We do have an overhead light as well as a table lamp, so we aren’t relying on our bookshelf lights to do more than illuminate the shelves and look good 😉
We purchased white Billy Bookcases in March, 2023 and found Home Depot’s Behr “Gallery White” to be a perfect match.
Great! Thanks for sharing!
Hello! We are hoping to build a bookcase very similar to this, thank you for such a great tutorial!
We are unclear on how the trim between the bookcases was done. Is the door in front of the trim between the bookcases, and if so how did you fill the gap between the door and the bookshelf? Did you make the bottommost shelf deeper?
Hi there! I show the bottom trim pieces we used in the original IKEA hack tutorial here:
https://thesommerhome.com/billy-bookcase-hack-tutorial/
And I show more detail in my Instagram highlight here:
https://www.instagram.com/stories/highlights/17849793676705204/
Thank you!
I did not see where you used the extensions?
The extension is the top shelf.