This post doesn’t really have much to do with decorating, but it does have to do with solving a problem that keeps my pets safe and my house cleaner. And I thought if I had this issue some of you might, too: How to keep the cat from using the dog door.
The issue was that I have a dog door, which my cocker spaniel Winston (in the picture above) has used for all of his life (10 years and counting).
I also have cats…somewhat large, long-haired, mostly-white cats that are meant to be indoor cats.
And they were indoor cats for the first 4 years of their lives until one of them (Chanel) figured out how to use the dog door.
Then I had one mostly-brown-with-leaves-tangled-in-her-fur outdoor cat.
Not only did she track all of that dirt into the house and onto the sofa, she also very quickly got into the habit of bringing me “presents” (ie. dead mice that appeared in the middle of the living room floor. Yuck!).
I was on the hunt to find a dog door solution that would let the dog go in and out, but keep the cat in.
My original thought was that there must be something I could buy to do this.
And I found three possible options, but each one had a couple of things that didn’t quite fit with what I wanted.
So I ended up modifying the dog door I already had and it seems to have done the trick (for less than $20 I might add)!
Keep reading to see the options I considered (one of them might work for you), and what I finally ended up doing.
Option 1: Buy a New Electronic Dog Door
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Electronic Dog Doors* are the ones that open up automatically when a pet wearing the trigger device on its collar gets close to the door.
They come in a variety of sizes, trigger mechanisms and installation options (I wanted one that fit in my sliding glass door space).
For this option, the receiver would fit on the dog’s collar and the cat would not have a receiver.
Then the door would open when the dog got close to it, but not for the cat…exactly what I wanted it to do! (Just make sure to get one that locks both ways, since some of them will let any animal go out the door, but require the receiver to get back in.)
If you’re interested in seeing how it works, you can go to the amazon.com page and watch the product videos.
The “pros” for this option are:
- None of the animals get shocked,
- It keeps out other animals and intruders (not that I have ever had a problem with that),
- And it’s kind of cool!
However, I decided the electronic dog door wasn’t the best option for me:
- First, it’s much more money than I wanted to pay (I already have a functioning dog door installed).
- The second reason is that I think the cat would learn how to get out anyhow. Chanel learned how to use the dog door in the first place by following right behind Winston as he went out. So I can just see her doing the exact same thing with the electronic door, and then not being able to get back in because the door wouldn’t open.
Option 2: Install Invisible Fence
My plan with this option would be to install an invisible fence outside the dog door.
Since I have a deck there, it would have been fairly easy to put the invisible fence wire between the deck and the house.
Then the cat could wear a collar with the shocking device on it, and the dog would not have the shocking device. So she would get zapped if she tried to go through the door and he wouldn’t.
The “pros” of this option are:
- It is fairly easy to install
- And it’s less expensive than buying a new dog door.
However, I also decided not to go with the invisible fence option:
- First, I wasn’t sure the shock would actually stop my cat. As everyone knows, cats are very different than dogs…and I read about people whose cats just sped up in order to get through the shock zone as quickly as possible (where most dogs try to avoid the shock). I was sure Chanel would be one of those cats!
- Second, I’m not that keen on zapping my pets with electricity, to begin with.
- And third, the instructions for the invisible fence say that the animals should only wear the shock device on their collar for a maximum of 12 hours a day. That means keeping the dog door closed for the other 12 hours. Since Winston is used to being able to go out whenever he wants to, that would mean either teaching a 10-year-old dog a new bathroom break schedule (not likely) or me getting up in the middle of the night to let him out (very likely).
Option 3: Lay Down a Scat Mat
Scat Mats are meant to keep pets off of things that you don’t want them going on.
It gives the animal a static shock when they try to step on it, somewhat similar to the invisible fence but in a mat format.
My plan was to put the mat inside the dog door to prevent the cat from getting to the door and going outside.
The “pros” of the scat mat are:
- It is really inexpensive
- And very easy to install.
But, as you probably guessed, I didn’t go with this one either.
- I was afraid that the mat would keep the dog away from the door more than it would discourage the cat. I think she would find a way around it (that cat personality thing again).
- And it has the zap-factor, which I don’t like that much.
Option 4: The DIY Dog Door Hack
My final solution was to modify the dog door that I already have.
My current dog door has magnets at the bottom of the flap which keep the door closed when it’s not in use.
I figured since the dog is stronger than the cat, all I have to do is add enough magnet strength so that the cat couldn’t open the door, but the dog still could.
Step 1 | Watch The Cat
The first thing I did was to watch the cat as she was going out the door to see what she did and where she was pushing on it.
With my pets there is a difference in the way they open the dog door.
The dog just runs right through it.
The cat puts her paw through the edge of it to open the door and then slides her body through.
So my strategy was to place the magnets at about the height and location where the cat would normally be trying to push through.
She likes the right side better than the left, so I put 2 sets of magnets on that side…I probably could have got away without the second set but I’m not taking any chances 🙂
Note: Your cat may push the door in different spots than mine does, so you might have to put the magnets in different locations.
Watch to see what their favorite spots are. Then place your magnets in those areas of the door.
Step 2 | Get The Supplies
After a few trips to the hardware store, I ended up with these bits:
- larger magnets with screw holes in the casing at each end*,
- smaller magnets with holes through the middle.*
- #10 x 5/8″ screws* to attach the larger magnets to the door.
- #6 – 32 tpi x 2″ screws* to attach the smaller magnets to the flap (you could probably get away with shorter ones than these…this is what they had in stock at my local store).
- #6 – 32 tpi lock nuts* for the longer screws.
Since I added the magnets in 3 places on the door, I used 3 of the larger magnets and 6 of the smaller ones.
You can adjust the number you need based on the size of your animals 🙂
I would start with 2 sets of each (one for each side of the flap) and then go from there.
Step 3 | Attach the Magnets to the Door
I used the 5/8″ screws to attach the larger magnet to the frame of the dog door.
Then I cut the edge of the plastic off on the dog door flap so that it fits around the magnets on the frame.
Finally, I attached one small magnet on either side of the flap so that the edge of those magnets would meet up with the large magnet.
Make sure that you have them pointing the right way so that the magnets on the flap stick to the magnets on the frame.
Because these magnets had a hole in the middle, I used a screw and nut to attach them to the flap.
If the end of the screw sticks out on the other side, you might want to cut it off so that it doesn’t poke your dog when he’s coming through the door.
The dog door “hack” has been in place for a few years now, and the cat seems to have given up trying to escape. Success!! Even better, the entire project cost less than $20.
Have comments or questions about how to keep the cat from using the dog door? Tell us in the section below
This post was originally published on September 16, 2015 but was updated with new content on January 14, 2023.