Cat Owners - Having a vented automated litter box


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Cat Owners - Having a vented automated litter box to eliminate odors

Use this How-To at your own risk and discretion. Only you know the skill level you posses for Do-It-Yourself projects. Please check your local codes.

Second I must post a disclaimer. The pictures show the ‘rough’ finish. The finish work and touch ups have not yet been done.

Cats are amazing creatures and most people have a very firm opinion about these little predators. Either you love them or dislike them. I personally have two cats and I consider them a part of our family. The one thing I don’t like about cats is the litter box and the odors that the litter box emits. So for you cat lovers out there here is a quick How-To on how to eliminate those odors that are the tell tale sign of a cat owner.
No one that visits our household knows we have cats.

There are a few prerequisites and assumptions in this write up. They are:
1. You have a closet or small room you can place the litter box in to build a small enclosure.
2. You have convenient way to run vent pipes outside or into an attic.
3. You have access to an electrical outlet.

Overview of installation environment:
In the corner of our Entertainment room is a small closet that has both a door and an adjoining wall with the Entertainment room. The closet itself has electric; I had an electrician install an outlet by the box. Above the closet and room is an accessible attic.

What you will need.
1. (Optional) You can try to retrofit your current litter box into an automatic one but I suggest you get a Littermaid litter box. It cuts down on the number of times a week the litter box needs to be changed and helps suppress odors. You can find them cheapest on eBay.
2. A pet door.
3. A sheet of plywood or MDF and some 2x3’s. You will need to determine the amount of materials that you will need, these are suggestions.
4. Handles and a locking hasp. Screws. Liquid nails (if you can’t nail into floor)
5. A bathroom exhaust fan. You can find these at Home Depot. I paid about $11 for mine. Aluminum vent pipe and assorted elbow pieces and a cap for the end of the vent pipe. (The pipe cap I bought was a solid piece that I drilled holes through). This was done so nothing would fall into the vent while I was installing it into the attic and clog the vent.
6. Extra electrical cord and a 2 prong plug. This also can be found at Home Depot. I bought about 5 feet of cord, your needs will vary. Wire nuts and electrical tape.
Note: You will need this to extend the power cord from the exhaust fan to an outlet.
7. A motion sensor and transceiver.
Consider a 2-way transceiver for flexibility running events and macros.

Let’s get started.
The first thing we will do is to install the pet door. You can do this one of two ways.
1. Install the pet door in the closet door itself.
2. (What I did) Install the pet door in the adjoining wall. It was narrow enough to fit between the studs. (See Pic 1)


Installing the Pet Door
Follow the directions that came with the pet door for installation instructions.
These doors come with a paper template so you can trace the outline of your pet door on the wall (or door) so you door will fit perfectly.
Note: If you install the pet door into the closet door all the steps needed for the installation will be found in the instructions and should be easy and shouldn’t take long.
If you are installing the pet door into the wall you will need to do a few things that won’t be found in the instructions but aren’t difficult to do. Once you cut the hole in the sheetrock (on both sides if applicable) you will need to use 1x4’s (or similar) to box out the gap between the sheetrock (See Pic 8). This must be done because the pet door isn’t designed to be installed with such a wide gap between the 2 halves of the pet door. Without the 1x4 framing the cat(s) may be able to slip through the gap into the wall. If you never done something like this before it’s pretty simple. Just measure and cut the wood to match the length of each of the four sides. Then ‘slip’ the respective pieces in place and hold them in place with a small nail or two on either side.
Now you can finish installing your pet door.


Modifying the Exhaust Fan
Before we start on building the box lets modify the fan so we can be ready it to install into the box and plug into transceiver module. It’s easiest to install the fan while you build your box enclosure so we must ready the fan for installation.
Most fans come with the motor\fan assembly and a aluminum pan that is installed into the ceiling, though we will install the aluminum pan into one of the (yet to build) box walls.
When you remove the motor and fan blade assembly you will notice the assembly has a small length of cord with a regular 2 prong plug. You will also notice that the aluminum pan has a regular 2 prong outlet to plug the fan into. How this normally works is that the 2 prong outlet installed in the aluminum pan has 3 wires on the reverse side of the outlet. These are for hardwiring this 2 prong outlet to an electrical supply. We will not need this part as we will be plugging the fan directly into a transceiver unit. So you may remove the 2 prong outlet and wiring assembly altogether.
Start to modify by cutting the plug off the end of the small length of cord on the motor assembly. Now take your length of cord you bought and splice it onto the small length attached to the motor assembly. Use the wire nuts for a good connection. Now if you are anal you can use the electrical tape to secure on the wire nuts and nicely tape up the connection area. Run the wire out through the back of the aluminum box. On the other end of the length install the new 2 prong plug you bought at the store. Now we are ready for the box.

Building the Box
Once you have the pet door installed and the fan modified you can start framing out a box on the inside of the closet. Please make sure you measure the litter box for your INSIDE dimensions and remember to leave some room for the cat to be able to walk into the litter box, don’t make it too Closter phobic. Be as generous as you can with the inside dimensions, remember you also are going to need room inside to clean and refill the litter box. Also be aware that one side of the box will need to be removable.
Framing the enclosure can be done with 2x3’s and plywood or MDF (Medium Density Fiberboard). Like most things this can be done several ways. You can either frame and sheath an entire ‘true’ box and install in into the closet. Or you can attach 2x3’s directly to studs in the closet and ‘box’ it out and sheath it that way.(see Pic 4 and Pic 5) Keep in mind the placement you of your exhaust fan. It will probably be easier to install the fan while you are building the box rather than after. Also remember you will need to attach an aluminum vent elbow or flex piece to the back of the fan so make sure you leave room for that. (See Pic 2) Please follow the instructions that came with the fan for installation. I installed my fan on the back wall so I could use the top of the box to store the litter and other pet supplies. (See Pic 7)





At this point it should be mentioned that one side of the box will be a removable door. See Pic 3 for the overall view of the box already built. From this picture you will notice that two of the sides are ‘permanent’ and one is removable. You will also notice the installation location for the handles and hasp lock. In Pic 3 and Pic 6 you will notice a slotted piece that was glued to the floor to act as an anchor for the bottom of the removable door.


Hang on now you’re almost done. Now install the vent pipe from the fan into the attic by cutting a small hole in the ceiling and fitting through the vent pipe. (See Pic 9) I used a small cap (with holes) on the end in the attic so nothing would fall down and clog the vent pipe.



Once your box is built and sheathed and the fan is installed it is now time for the easy part. Configure your transceiver’s address and plug it into the outlet. Now configure your motion sensor with the address of your transceiver (read instructions that came with the sensor) and install it somewhere inside the box. (See Pic 4) You can set the timer on the motion sensor at your discretion but I have it set for about ten minutes. This means the fan turns on when the cat enters the box and won't turn off until the motion sensor sends the 'off' command ten minutes after the cat leaves the box.
I use HAL2000 for my HA software so I can also use voice commands to turn the cat fan on and off. But you also can use Macro’s to trigger all sorts of events. In the beginning I had a macro that text messaged my wife every time the cats used the litter box.
Now your home will be litter box odor free.

What do you "outdoor" cat owners do about the garage door being open for the cat. Do any of you guys use one of the "flap" style doors?
Something is wrong with your server, firewall, etc... It has nothing to do with the way you are posting them in your thread.

Are you port forwarding correctly? Are they on your Home Machine? Behind firewall?
I don't seem to have a problem access them from home or work.
No there is no port forwarding. The firewall is also a web server. I will have to take a look at my settings...
OK AberdeenKid, here is the problem with your pictures in your thread.

You need a security certificate to be accepted from your site. It takes forever to finally display the security accepting message, but once you do, you will now see some pictures.

I had to edit your post so link typos were eliminated and the pics pointed to https:// instead of http://.

BTW, your security certificate isn't recongized by Windows. Not sure how many will want to accept it. I did since I am a trusting soul and you were just displaying links to jpg's.

OOPs.... My firewall crashed a few weeks ago and I had to replace it with an old image. I didn’t know it was requiring a certificate..sorry about that I guess I need to check my settings. As for Windows not accepting the certificate. Its a Unix firewall and we all know how wonderful windows security is. Thanks for the fix.
Interesting! DId you have any trouble getting your cat to notice it? I mean it is kind of hidden... I wonder if you could put newpaper in it for the small dogs to use? Im not a pt person my self. My fiance keeps wanting me to agree on a small dog but i have not gave in yet.
You certainly built one heck of a litter box or did you say storm shelter. :p

My cats litter box is in the neighbors flower beds. ;)
Interesting! DId you have any trouble getting your cat to notice it? I mean it is kind of hidden... I wonder if you could put newpaper in it for the small dogs to use? Im not a pt person my self. My fiance keeps wanting me to agree on a small dog but i have not gave in yet.

Interesting! DId you have any trouble getting your cat to notice it?
Not at all. Cats are great to house break. You just show them where the litter box is and they will use it with no prompting. We have two cats, all my wife and I did was shut the door to the room the box used to be then take the cats downstairs to the box's new location. That was it.
I wonder if you could put newpaper in it for the small dogs to use?
If you are getting a small dog you could train it to use a litter box just like a cat. it probably make your life a bit easier.