
This is the first phase of the automatic chicken coop door conversion project. I will be using the Add A Motor D20 chicken coop door motor. Update: You can read about phase two of the automatic chicken coop door conversion.
I have an existing coop. That means I need to convert the existing chicken door into an automatic door. To do this I designed a door cover that completely covers the existing entrance to the coop when installed.
I decided to approach this project in two phases. The first phase is to construct the automatic door. The second phase will be to install it into the chicken coop.
I took pictures while working on phase one and have provided step by step instructions below.
Step One
The automatic chicken door will be mounted to a piece of half inch plywood. The first step is to measure the door cover using a chalk line. Then it can be cut out using a circular saw.

Step Two
The second step is to measure the door opening and mark it with a pencil using a straight edge.

Step Three
Next, cut out the door opening using a circular saw.

Step Four
Make a new door. The new door should be one inch wider than the door opening. This will allow the door to completely cover the opening. The door will be held in place by the door rails.

Step Five
Next, you will need to fabricate door rails for the new door to slide up and down in. I used 2×2 lumber and 3/8 inch rabbet bit in a router to make the door rails. I made three passes with the router, removing more wood with each pass.

Step Six
Attaching the door rails to the door cover is the next step. I nailed the rails in place.

Step Seven
The next step is to mount the bracket for the Add A Motor D20 chicken coop door opener. According to the installation instructions, this bracket should be mounted the height of the door plus ten inches above the door. In my case, I designed an 8 inch tall door. I mounted the bracket 10 + 8 = 18 inches above the door. I had height constraints because I am installing into my existing coop.
This is the information I wish I had when I built the coop this spring. I could have left enough room for the door during the initial construction, instead of having to make the door cover.

Step Eight
Attach the motor to the mounting bracket.

Step Nine
Installing the sealing washer is the next step.The sealing washer attaches to the new door one inch below the top of the door in the center of the door. This is what holds the lift cable that is used to raise and lower the door.
I had to use a wood screw that I had on hand. The wood screw was longer than half an inch. This means it stuck out the back of the new door. This is a problem because it will prevent the door from easily sliding in the door rails.

Step Ten
In order to shorten the wood screw, I used bolt cutters to trim it.

Step Eleven
Now that the motor is mounted and the sealing washer is attached to the new door, the door travel can be adjusted. The provided installation instructions explain how to do this step. I have shown the door in the open position below.

Step Twelve
Next apply power to the motor to test the close operation.

Questions or Comments?
Please leave a reply below if you have any questions or comments.
I have a question about your automatic chicken coop door: Is it possible for a predator to somehow lift the door upwards when it is in the down position?
What holds the door against the board the door sits on in the down position?
Also, what is a “sealing washer” ?
Thank-you for answering my questions.
Mike Riesterer
@Mike,
I think the only predator that might possibly open the door from the out side is a raccoon because of its hands. But I think that would be a long shot. The predator would have to push the door against the rails and then upwards. I don’t think it is something that a raccoon would figure out on their own.
In actuality, I have lost chickens to a raccoon before because I forgot to close the coop door at night. The automatic door solves the problem of me forgetting to close the door at night.
Gravity holds the door in the down position. There is no locking mechanism in the down position. This can be seen more easily in my post about phase two of this project.
The sealing washer came with the motor. It is basically a washer with a rubber gasket on one side. The lift cable is attached to the door with the sealing washer. Basically the lift cable is held against the door by a piece of rubber. If the door gets stuck, the lift cable will strip out of the sealing washer. The motor will then run until it reaches the stop position. But the door will not open. This design prevents damage to the motor if the door gets stuck.