Introduction: "Dog Proof" Cat Litter Box

Picture of "Dog Proof" Cat Litter Box

Litter pans are a problem.  Especially when you have a large cat who can't fit in a small litter box and a dog who considers cat poop a delicacy.  It's been a struggle to find a commercial litter box the cat can enter and the dog can't.  As a result, I decided to make my own using 2 storage crates I purchased from Wal-Mart for around $20.  The smaller crate sits inside the larger one creating a "foyer" so dogs can't reach the litter pan.  The roomy crate is large enough even for big male cats who have poor aim.

"Dog Proof" may not be as accurate as "Dog Resistent" or "Dog Challenging", but so far it has worked well in our household.  In fact, our dog has given up on raiding the litter pan so I consider it a complete success.  We have large retrievers who are much too big to fit through the doors, although small breed dogs could walk into the litter box just like a cat.  By altering the size of the door openings, however, this design should accommodate many cats & dogs.  Another feature of having a box with a "foyer" is most of the litter on your cat's feet will stay inside the large crate as they exit. 

Let me show how to build this inexpensive litter box for your cat...and not your dog.

Step 1: Stuff You'll Need ...

Picture of Stuff You'll Need ...

This project requires very little in materials and tools to complete.  Here's a list:

30 gallon storage crate
18 gallon storage crate
The 2 crates need to be similarly shaped so they seat nicely together.

1 1/2" hole saw & drill
Scrap wood
4 wood screws
Small piece of mat or carpet

Step 2: Creating the Foyer

Picture of Creating the Foyer

Before cutting the holes in the crates, I made a false floor in the foyer to anchor the inner pan at the rear of the larger crate.  The distance between the fronts prevents dogs from being able to reach the litter pan.  In the first pic, the bottom board is a 2x6 and the top board is 1/2" plywood.  Use 3 or 4 wood screws to secure the boards together.  The combined thickness of the 2 boards and mat is 3 1/2" thick.  The boards and mat can be removed for cleaning.

Step 3: Cutting the Doors

Picture of Cutting the Doors

Because our cat is a big male, I made the doors somewhat large knowing our dogs wouldn't be able to enter.  The doors are 5 1/2" wide and 8 1/2" tall.  Alternatively, you could cut a circle if you have a smaller dog who likes to raid the pan.  Using the false floor and mat as a guide, I used a 3/4" scrap board to mark the bottom of both doors.  This insures the floor is below the bottom of the door and allows for adding a piece of carpet in the future.  Carpet would do a better job of removing cat litter as your cat exits the pan.  The door lip also allows for a 4" deep inner pan to hold the litter.

Once the door dimensions were marked, I also marked points 3/4" from each corner for drilling the 1 1/2" holes.  This is primarily for appearance and you could simply freehand the door opening also.  Pic 2 shows the 4 holes and I used my jigsaw to cut between the holes and complete the door openings.  The top cut is much easier to make from inside the box.  A file was used to smooth the cuts and remove any burrs.  Pic 3 shows the completed opening and foyer.

Step 4: Let There Be Light!

Picture of Let There Be Light!

In my experience, some cats don't like dark caverns so I added some holes in the top for light.  I used my 1 1/2" holesaw again to make 8 holes along the outside edges.  Pic 2 shows the interior of the box with the lid in place.  

All you need now is some litter and a quick prayer your cat will actually use it.  Cats can be picky but what's not to love about this box.  Our cat, who is very particular, has been very happy and we've been pleased to not have the dogs in the litter box anymore.  Hope this cheap & easy project makes your critters happy as well!


irish21450 (author)2017-08-01

I have to try this!!!

RunaeG (author)2017-05-30

This is a great idea, but it doesn't help with a small Torkie. They could still get into the kitty liter box.

BrittanyS71 made it! (author)2017-03-12

I just finished this project. Didn't have a hole saw, but a big knife worked just fine if you have half and hour. I put the entry hole into the side on the left. Cat could get in and take a right into litter box. Dog has no chance. What a great idea!

kentdvm (author)BrittanyS712017-03-29

Looks great! I like the shape of the opening very much. Good job!

RuthT29 (author)2016-09-21

this is brilliant! My dog just barfed up cat poop all over my lap, and he was nearly banished to the outside, had I not found this. Going to get my storage tubs now!! Thank you very much!

LoraR3 (author)2016-08-03

I have a "full figured" cat and a sneaky poop-eating dog. We had to open the door on the pet gate so she can get through, but the dog can get through too! This is a GREAT solution!!

MichelleS289 (author)2016-07-11

I need this in my life. You may be a Genius. I mean I have a baby gate to gate the litter off, of course my husband can't keep the bloody thing closed. But this. This may be the answer.

Djplay (author)2016-05-10

Great idea. FYI, I struggled forever on keeping my dog out of the cats litter box and finally found this product and it might solve your problem. I have had it up about 4 months and it has worked surprisingly well. My dog has yet to enter the laundry room were I have it and my cat goes in and out all the time. If you want to check it out it was at:

kaksamit (author)2016-03-26

I LOVE this idea - we have two cats that intimidate each other when they see the other using the box, one cat that is a standing pee-er, and a dog who wants all the poop candies with pee-flavored sprinkles. We've tried every high-sided, covered box that we have been able to find but still have issues because of the standing pee-er. Her urine always gets in the gap between the cover and the box, proceeding to leak all over the floor. Gross! I think this will be a perfect solution. Thanks for the instructable!

Question: Did you need to file down the cut plastic at all? it sharp?

kentdvm (author)kaksamit2016-03-27

Great! I hope it works for you. You don't need to file it just fold a piece of medium grit (120/150) sand paper over the edge and sand it. That's enough remove burs. Good luck!

OliveV (author)2016-02-08

Thank you for this genius idea! I made one over the weekend and so far so good!

kentdvm (author)OliveV2016-02-09


csimon2 (author)2015-08-18

Couldnt you simplify this by putting your existing litter pan in the outer tub? (Assuming the dog is larger than the outer hole)

kentdvm (author)csimon22015-08-20

You could. One of our dogs pushed too hard through outer door and would collapse it inward. Using another tub inside prevented that happening and increased the distance of litter pan from entrance.

MrsBleezzy (author)2015-08-18

You are a genius! I have the same problem with my dogs, and they eat it on my bed, yuk! I bet this also keeps more litter inside vs out. Can't wait to try this, thanks

Plexxy (author)2015-04-23

I absolutely love this idea! What's crazy is that we don't have a dog, but a toddler! A curious toddler! Definitely going to try this

UwishUcould (author)2015-02-20

I have two cats. I have looked and looked for a solution to the odor. My dog, a Puggle, does not mess with their poo, thank God. We recently bought a new home, and I did not want the cats to track any litter around in it. This is such a neat idea, that I am making it tomorrow! I agree that pet supply manufacturers should be mass producing this! What cat owner wouldn't give to get rid of cat odor. Thank you so much for this idea! Many blessings to you, and yes, I voted for this!

crank_girl (author)2014-06-07

Great idea! Gonna have to modify to keep my wily and small jack russell out though. I also think I'd put a bit of plexiglass across the top as I can't see my rather fussy cat going in otherwise.

PMStubbs (author)2014-04-22

The foam around the edge is a nice touch, but if you could put an edge that would "brush" the cat when it went in and out, it would help groom the cat and save time cleaning the upholstery. Love the idea, because my dogs think our cats are little pez dispensers too. Now if we could figure out how to keep them out of the stalls in the barn!

kentdvm (author)PMStubbs2014-04-23

Good idea. Even carpet would help knock it off their feet. We have horses also and that is primo stuff to our dogs too.

antdada (author)2013-01-28

I did the same basic design! You can paint the outside of it also to match your bathroom. I'm going to do Pumpkins lite blue container with grass and flowers on it! Also you can split a foam pipe and put around the cut out doors to give it a finished look! :) It's GREAT Idea!

srkleinpeter (author)antdada2014-01-19

I am so glad you mentioned finishing the edges with the foam pipes. I cannot wait to try this!! This may forever change our lives!

ejsilver26 (author)2013-12-31

Would you be able to off-set the doors to make it a bit harder to go directly in? I like this design as well, as we had that problem as well. We "solved" it by putting the litter box in the basement, and the dogs don't go down there. Only problem is that we rarely go down there so it doesn't get cleaned often enough anymore. I might try your solution. Thanks for a great 'ible.

dwilliams80 (author)2013-11-15

This is a great idea, but my 17 lb cat is bigger than my 14 lb dog. I had a top entry catbox that worked great till my cat refused to use. Any suggestions would be welcome. Thought about top entry on the outer box and then front door on inner box.

kentdvm (author)dwilliams802013-11-16

An opening in the top would work just fine. Another idea would be to get the litter box off the floor so your cat had to climb up to it. You could build it into a perch or kitty "jungle gym". Good luck!

postula89 (author)2013-09-07

How do you clean it? Does it come apart?
I love the idea because my dog eats the poop as well. Also my older cat does not have good aim anymore.

kentdvm (author)postula892013-09-09

The inside tub lifts out. This has worked very well for us and our dogs. Good luck!

DustBunny (author)2013-01-13

I also like the fact that it doesn't look like a litter box.

sixsixzero (author)2013-01-10

Love it !

Slay. (author)2013-01-07

Hey, i loved your instructable so i voted for it! If you like mine you should vote for it too at:

sheryle (author)2013-01-05

we are going to try this ASAP. I hope works

russ_hensel (author)2013-01-04

Really nice work, I am inpressed.

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