How to Install a Hidden Door Leading to Your Home’s Secret Passage

C.E. Larusso
Written by C.E. Larusso
Updated November 29, 2021
A bookcase secret door
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Make your hidden door fantasy a reality with these steps

Maybe you have valuables you need to conceal. Maybe you want to create something special and fun for the kids. Or maybe you’ve just wanted to be a real-life Miss Scarlet or Colonel Mustard since the first time you played Clue. There are many different reasons you might want to build a hidden door in your home.

If you have a small passageway, like a servant’s staircase, a large closet, or a basement or attic landing, you can build and install a hidden door yourself and turn an ordinary space into a secret passage.

There are a variety of different ways to conceal a hidden door. This step-by-step guide will focus on how to install a swinging door that appears to be nothing more than an accent wall, but can be pushed open to gain entry to a secret room by those in the know.

Difficulty: 4/5 Time: Two daysTools and materials needed:

  • Butler door/swinging door hardware

  • Chisel

  • Clamps

  • Diagonal pliers

  • Drill

  • Forstner bit

  • Hammer

  • Interior slab door

  • Jigsaw

  • Level

  • Mallet

  • Miter saw

  • Nails

  • Paintbrush

  • Plumb bob

  • Pneumatic brad nailer

  • Putty knife

  • Router (45-degree chamfer bit; half-inch straight bit)

  • Screwdriver

  • Tape measure

  • Utility knife

  • Wood glue

  • Woodworking compass

1. Prepare the Doorway

If you’re DIY savvy (this project is advanced!) and have carpentry experience, you might be able to build your own hidden door. If not, you’re better off hiring a local door installation pro to ensure your safety and proper installation.

Before assembling and installing your new secret door, you must first prepare the doorway by removing the existing door and doorstops.

  • Remove the doorknob and lockset.

  • Find the bottom of the center cylinder on the middle hinge and place a nail, tapping gently with a hammer to loosen and remove from the top. Repeat these steps with the other hinges, and then pull the door free.

  • On the jamb, locate the doorstop, looking for the two vertical pieces with beveled sides. Using the tip of a utility knife, trace around the perimeter of the stop, scoring it. Find the edges of the doorstop at the point where it connects to the jamb on the sides, and slice in on all sides, cut away any paint buildup.

  • Once you have created enough space, insert a putty knife between the doorstop and the jamb and begin gently prying until you’ve widened the space enough to insert the tip of a screwdriver.

  • Now with the screwdriver, keep prying until the stop is lifted from the jamb, leaving a crack at least one-quarter of an inch wide. Move the screwdriver up and down, creating more space until you can insert your fingers to pull the stop completely off the jamb.

  • With diagonal pliers, remove any remaining nails. 

  • If there are any gaps, apply wood filler and, once dry, sand until smooth.

  • Repeat these steps to remove the two remaining vertical stops.

 Your doorway is now ready for a door that can swing in both directions.

2. Hang the Swinging Door

Before you can abscond into your hidden room, you’ve got to hang your swinging door.

  • Take the pin socket from your hardware kit and trace an outline on the top door jamb. Referring to the hardware manufacturer’s instructions, add an extra half-inch inset from the side jamb. Measure the door and recess the pin hardware at half its thickness. These adjustments will help conceal your secret door.

  • Drill overlapping holes with a Forstner bit until you can push the socket in. Once you’ve confirmed the location is correct, secure the hardware with one-inch wood screws.

  • Install the pin at the top of the door. On the bottom corner of the door, trace an outline of the floor hinge hardware. Using a jigsaw, cut out a notch. Attach and secure the hardware with screws.

  • Through the pinhole in the top socket, drop a plumb bob and mark its place on the floor. Set the door in place and place the pin into the socket. 

  • Set the floor hinge hardware around the mark you left. 

  • Prop the door open and use a level to make sure it sits fully plumb before fixing the hardware to the floor with 1-inch wood screws.

3. Install the Baseboards

Baseboards will play a crucial role as you build your hidden door.

  • Measure from the closest baseboard to the edge of the door. Cut a new baseboard to the required length. 

  • On the end of the baseboard that bridges the gap between the door and the jamb, make a 45-degree miter cut in the direction of the gap.

  • Attach the new baseboard to the wall using wood glue, and then secure it with 18-gauge brads using a pneumatic gun.

Once completed, repeat these steps with the opposite baseboard. 

  • Next, measure the space between the baseboards. Cut a piece of wood to fit the space, with straight edges at each end, using a miter saw to cut the bottom of the wood to fit.

  • Hold the new baseboard with the back against the floor hinge hardware, and tap the front with a hammer until the hardware has left a mark in the back, and then trace an outline for the required recess. 

  • Place the baseboard on your work surface and secure it with a clamp. Insert a quarter-inch straight bit into your router, begin routing following the outlines of your recess and then rout out the wood within the outline.  

  • With the new recess, fit the baseboard against your door, making sure it aligns with the other boards and rests flush against the door. Glue and tack into place.

Tip: If you don’t have a router, you can create the recess with a one-inch chisel and mallet.

4. Cut and Install Side Stiles

The stiles will house the door’s locking hardware. Here are the steps to take to keep things locked up in style.

  • Create space for the side stiles to meet the baseboard by creating notches in the base cap molding in each wall. 

  • Create a guide with a half-inch scrap of wood, hold it against the door wall and make the cut with your chisel.

  • Measure from the top of the baseboard to the ceiling and cut two stiles to length. On one side of the topmost jamb, mark where the side still will cross, looking for the point where the stile will conceal the gap without preventing the door from swinging.

  • You will need to scribe the stile to make it fit—in other words, to mark the wood with a line precisely where it contours in place.

  • Set a wide board against the wall and make another mark where it meets the edge of the head jamb. 

  • Take a carpenter’s compass and set the legs between your two marks. Set your stile board plumb against the wall and move the compass along the wall side down to the baseboard to scribe the edge. Once completed, cut down the line using a circular saw.

Repeat on the opposite to create the second side stile.

5. Trace and Mark the Accent Pattern

Living room staircase with black accent wall
lawcain - stock.adobe.com

This is the step that will ultimately wow your guests. To make the hidden door appear as nothing more than an accent wall, you’ll need to add a center stile and rails.

  • On the door, trace a pattern for the center stile and four sets of rails, two on each side of the stile.

  • Holding up one side stile, mark the points where the rails meet the style. Repeat these steps with the stile on the opposite wall. 

  • Clamp the first side stile even with the table. Using a 45-degree piloted chamfer bit, use your router to cut a notch between the first set of marks, stopping just before you cut through the wood, leaving a thin face strip. Do the same between the second set of marks.  

  • With your 1-inch wood chisel and a wood file, clean and finish the notches.

  • Repeat these steps with the second side stile.

6. Install the Side Stiles

For the rest of the install, you’re going to be seeing stiles for miles.

  • To affix the first side stile, apply wood glue along the edge of the door jamb on the left side and to the back of the stile.

  • Once in place, confirm that the stile successfully obscures the gap between the door and the jamb, and tack into place with the brad gun. Repeat with the other style.  

7. Attach the Rails and Center Stile

By this point in the building process, your hidden door is starting to come to life.

  • Cut your rails and center stile according to the pattern you traced with the miter saw. Measure from the bottom line for the lower rail to the baseboard and cut two one-inch furring strips to length. 

  • Set the strips in place on the right side, add wood glue to your first lower rail and sit in place at the top of the strips. 

  • With the brad gun, tack the rail to the door. Remove the furring strips and set them on top of your lower right rail, repeating these steps to tack the upper rail into place.

  • Returning to your pattern, cut a one-half-by-4-foot center stile to length, from the top of the baseboard to the top of the door. 

  • Apply wood glue and press into place on the door, with the bottom meeting the baseboard and the right edges meeting the rails. 

  • Once in place, tack the stile to the door using 18-gauge brads.

After the center stile is secured, install the left side rails following the same steps.

8. Attach Top Rails and Stiles

To finish building your hidden door, you’ll need to install an additional set of rails and an extension of the center scribe on the wall space above the door.

  • Measure the space between the tops of the side stiles, and cut a top rail to length from a one-half-by-6-foot board. Glue and then tack it into place.

  • From the bottom of the top rail, measure to just below the door jamb, leaving only enough space for the door to open.

  • Cut to measure from lumber of the same size. Glue and tack the center stile extension in place. With the center stile extension in place, you can now measure for the lower rails that will flank the center stile on each side of the bottom.  

  • Cut to length and glue and tack in place. 

If the door frame has a diagonal outer edge, leaving a space between the top of one side stile and the top rail, you’ll need one more rail.

  • Measure and cut a one-half-by-6-foot rail to measure. 

  • Hold the rail in place. If the end overlaps the center stile or the place where the top of the wall meets the ceiling, mark the wood and use the miter saw to cut to fit. 

9. Paint to Match the Wall

Once all the pieces are installed, and look and function as they should, you’re ready to add the final touch. This is where things get really sneaky. 

Paint the hidden door and all rails and stiles in the same shade as the surrounding wall, creating the appearance of a small accent wall. 

You’ve now concealed your swinging door, hiding the entry to your new secret space to all but those who know to push!