Introduction: Hidden Bookcase Doors to Secret Lair
Every super villains evil lair need a secret entrance. That was the motivation for this project.
The design and construction was based on my own design. It wanted the doors to be fully functioning bookcases with a unique opening mechanism. They hinge inward and then slide outward. This way they don't take up room either inside or outside. I used maple hard wood for the strength and since other furniture in the room is maple colored.
Presentation was key.
Total cost in materials about $600.
This is my first Instructable so please mark it as a favorite. Thanks for looking!
Step 1: Reinforce Walls
When I pulled off the existing molding, there were weak shims holding the frame. I had to remove these and fill with solid wood on the top and sides since they will support a lot of weight.
Step 2: Surface Prep
After securing the frame to the studs with 3" deck screws, I needed to finish the wallboard to be smooth.
Step 3: Painting
Since I wanted the doors to look like book cases flush against the wall, I needed to fill the broken wallboard with joint compound, wet sand with a sponge until smooth and coat with primer and matching wall paint.
Step 4: Attach Hinges
Using these heavy duty hinges I found on Amazon, I shimmed them for easier placement. I bought 3" screws for added strength.
Step 5: Attach Slides
The 500lb full extension bearing slides were attached to the top and bottom of the hinged door. I determined that 14" slide movement was optimal.
Step 6: Attach Back of Bookcase
I test fitted and pre-drilled the back of the book case, this allowed precise alignment of both sides before the bookcase was built.
Step 7: Gluing and Clamping
This was the first bookcase I built. I drilled 5" holes to allow shelves to be adjustable. The sides were glued to the back using #10 biscuits (5 per side). The top and bottom were permanently glued in dado slots.
Step 8: Hang One Door
After 1 day to let the glue dry, one door was attached to its slides.
Step 9: Hang Both Doors
The 2nd door was attached to its slides. Some shelves were added. I allowed about 1/4" clearance between the back of the book case and the wall and on the top and bottom. This helps reduce the amount of light that could leak out and ruin the illusion. I may staple in black felt to further insulate them.
Step 10: Testing the Movement
The doors hinge inward and slide outward very easily on the bearings. I estimate each door is less than 100 lbs. Even when loaded with books, cds, dvds, etc. they should be less then the ratings.
Step 11: Holding the Doors Closed
To hold the doors closed I added two powerful magnets to brackets. I salvaged them from an old hard drive. Below them are a couple rubber end stops.
Step 12: View From Inside
Two small handles were added to allow closing from the inside. I could have spent more time choosing better wood but I didn't consider how the inside would look until completed.
So far, there is no sagging or rubbing on the carpet. The doors are very easy to open and close.
Here's a breakdown of the major parts (Lumber was mostly from Lowes).
Qty Item Cost
2 3/4" 4'x8' Maple plywood for door back $54 = $108
4 3/4" 8"x8' Maple board for sides $36= $144
16 1/2" 6"x4' Maple boards for shelves $12 = $192
2 Set of 3 Global Bearing Hinges $20 = $40
2 Pair of K&V Extra heavy duty slides $72 = $144
48 5mm shelf brakets $.75 = $36
1 5mm drill bits $10
Total: $552
Things left to do:
Finish wood:
I found wipe-on polyurethane keeps the natural wood color.
Automate opening/closing:
An arduino to control linear actuators to open the door when a "secret" button is pressed. PIR sensor to determine occupancy to prevent door from closing. If no occupancy for a set number of hours, doors should close.
Lair misc: Escape pod, obvious and accessible self-destruct mechanism, etc...

First Prize in the
Secret Doors and Compartments Contest
76 Comments
5 years ago
Niiice! This is one of the simpler secret door/room projects I've seen (with simple being a good thing!).
6 years ago
I love this project! I've been wanting to do this for some time now but wasn't sure how to go about it without purchasing a kit. But your instructions are great & seem easy to follow. I have 2 existing bookcases I want to use for this project & your instructions seem perfectly suited to doing just that. I'm not sure (you don't really state it clearly in your instructions) but it looks you used a separate smaller piece of wood as the door then attached the back of the bookcase to that. Is that correct? It seems to be in your instructions and in the photo of the back of the bookcases but the extra wood doesn't seem to be listed on your materials list either which is why I'm a bit confused. Could you please clarify that for me? And if you have any other suggestions for using existing bookcases I would welcome them gladly - I'm very much an amateur so I will be relying heavily on your instructions.
Reply 6 years ago
That's correct, you do need a plywood 'door' that attaches to the hinges and provides a mount for the slides. Mine were cut from the remainder of the same 4'x8' plywood used in the book shelve backing.
If you are to use existing bookcases, note that your backing will probably be very thin plywood that won't be strong enough to support the loaded case and will need to be replaced with 3/4" plywood.
Good luck!
6 years ago
This instructable is amazing! 10/10 would build, if I had the money! (:
7 years ago
this would be a great way to hide the rest of the house rooms in my house my Dads room is right off the kitchen :-/ this would be a great way to hide the room from the kitchen/dining room :-) puls hide the back door too as this would also be a great way to keep in some heat during the winter :-) humm I can see I will be doing this to most of the rooms in the house I like the idea of extra shelving and space but hiding rooms when you have guests over :-)
Reply 6 years ago
Wouldn't your dad see the new bookshelf in the doorway?
Reply 6 years ago
lol yep but the idea is to change his bedroom door from the kitchen side so that when we have guests over, all they see is the bookshelf and not a door this would make the kitchen/dinning room look a let less like the throughafare and more like a room at the moment it has 4 doors at one end of the room on three of the Walls by changing them to look like bookshelves it won't look so yuck.
All of the house leads into the kitchen/dinning room too many doors I hate the look of it but by changing the the doors too moving bookshelves it will give it a warmer and nicer feel to the room. In one corner of the room it has three doors all ontop of each other and thus has wasted space in that corner but by changing the doors to a bookshelf each then it will nolonger be a wasted space.
Reply 6 years ago
I see... good idea!
7 years ago
The door is so cool. I now have a brother free hideout
7 years ago
Great 'ible! First have secret lair, however! Ha ha! Love it
7 years ago
Wow! what fun - and what a beautiful job you've done! Thanks so much for sharing it. I would love to incorporate some of your ideas for my son & daughter-in-law's room. I hope you keep instructabling.
7 years ago
I didn't even look at all the steps! Couldn't wait to compliment your ingenuousness with this. Your design also eliminates the posibility of marks on the floor indicating the presence of a moving ability on what appears to be a fixed stationary object. I say, job well done good sir! Oh ya, I also favorited this.
7 years ago
Love it I'm totally doing this
7 years ago
awesome for a first instructable!
7 years ago
Given the cost of some doors...totally worth it. I will have to bookmark this until I have the house to justify having this.
7 years ago
Some friends of mine asked me to build something like this for them. I have been puzzling over how to make it work and you solved that problem for me with the drawer slides. Ingenious. Also, the re-purposed disk drive magnets are an excellent idea. I have a dozen old disk drives gathering dust in my office... Excellent work.
7 years ago
Years a go my parents had a cabin somewhat in the middle of nowhere. Some homeless locals or somebody knew my parents only went up there for a week during deer hunting season and a couple times in the summer. When my parents went up there one summer they discovered people had been living there but they didn't see the secret area that was built something like this. My parents really thought it was amazing they didn't discover it.
7 years ago
Wow. That is so cool. It is seamless and not at all obvious.
7 years ago
If you're having trouble keeping knicknacks on the shelves, museum wax might help: http://thd.co/1QVVSvD
7 years ago
Niiice! Hey, a secret lair like that could save your life in the event of a zombie apocalypse or terrorist ninja attack! Now it needs something diabolically clever to activate a secret latch-release mechanism, like twisting a piece of trim or something.