RV Mods: An access door for your cat — or dog



By Russ and Tiña De Maris

We’re not sure where to lay our (pardon) paws on any hard statistical information, but if an eyeball survey of RVers carries any weight, a lot of you are traveling with cats. These furry little bed warmers can be welcome traveling companions, but they also come with their own set of issues. For one, where does one install the cat biffy? Some place it in the shower stall – which may not be such a bad location provided the door doesn’t close, locking Fluffy away from her bidet.

RV Mods: An access door for your cat -- or dogAt one point, our traveling research rig was a truck camper — a far cry from the space afforded by our full-timing fifth wheel. The idea of having a litter box underfoot in those limited few square feet of floor space was just unthinkable. There was, however, a plethora of space available outside the camper, yet still enclosed by the truck bed, in the wheel well area of the truck. The camper manufacturer had made that space available by putting access doors through the sidewall at floor level, but the thought of leaving one of those doors open to allow Ithmah (our cat) in and out only stirred visions of blasts of hot or cold air, depending on the season. Tripping over that open portal—especially during dark night trips to our own “sandbox” didn’t sit well either.

The solution was waiting at the big box building center: A small “pet door” installed in the existing access door would allow our friend to go to her powder room, while the clear flap on the pet door would (generally) keep the outside and inside temperatures segregated.

What to do when the truck and the camper were separated? We’ve had some experience in this field — our fifth wheel was equipped with a pet door just under the dinette table; outside that pet portal lies another litter box — but this one cleverly assigned to our “Kitty Kondo.” The condo, which can be dismantled to lay flat for transport, is a secure “Arizona Room” with screened walls and rain-shedding roof, almost sized correctly. Actually, the condo was designed for Ithmah’s predecessor, who weighed in at a “whopping” 6 pounds wet; Ithmah tips the scales at 17 pounds, so the condo could stand to be a bit bigger. For our “research vessel” we had another, more appropriately sized condo constructed to cling to the side of the camper box.

After the truck camper became unworkable (too many steps up to bed for tired bones), we swapped over to a travel trailer. Here a small pet door was cut into a storage compartment that housed the rig’s batteries. There was space for the sandbox, and we carefully built a cover over the top of the batteries to prevent cat paws from coming into contact with the batteries. Later, from the same compartment through the outside wall, we put in yet another pet door to an outside condo unit. With the condo in place, her nibs has to make the trip through two doors to reach the cat pan, but so far, she hasn’t filed any complaints.

How can this work for you? It may be a matter of stretching your imagination out a little bit. Does your motorhome or trailer have basement storage that shares a common wall? Imagine a pet door allowing your feline friend to access his bathroom 24 hours a day without assistance. Or perhaps you travel with a more independent canine companion. Where it’s safe and neighborly to do so, an appropriately placed “doggy door” could allow your hound access to the great outdoors.

The Mechanics of It All

Adding a pet door to our existing access door wasn’t all that difficult. It does require some careful planning, and measuring. Since walls (and doors) in many RVs are a lot thinner than in conventional land-based homes, you’ll probably need to add framing around the perimeter of the “cutout” hole you make for the pet door. In our case, 1 x 2 lumber, laid flat against the existing door, was plenty thick enough to meet the pet door’s requirements. But in haste to get the job done, the distance from the edge of the existing door wasn’t taken into account. The full width of the 1 x 2 didn’t allow the original door to close. Carefully splitting the offending 1 x 2 in half solved that problem—but it goes to show the old saw is still valid: measure twice, cut once.

When installing a pet door through an RV wall, more caution needs to be exercised: Are there “vital organs” that might be in the way? Consider the possibility of water lines or electrical wiring. If in doubt, consult with an RV professional before sticking the saw tip in the wall. You’ll also need to carefully apply sealant between the exterior wall and the pet door pieces to keep the weather out.

Picking out the right door is important too. Most pet doors allow for a method of securing the door to keep out (or in) your animal companion. It’s also helpful to keep out stray critters—who needs a squirrel running around in their rig?

For the most part, the actual installation of a pet door is pretty straightforward, and the doors come with instructions — and usually cutting templates — from the factory. You’ll likely need access to a drill and bits, plus an appropriate cutting saw. While most instructions call for a simple saber saw, if you’re cutting through fiberglass or metal siding, you might be in need of reciprocating saw — a “sawsall,” as most refer to it in the trade. Of course, when installing a pet door anywhere in the rig, keep in mind the future sale of your rig and take resale value into consideration.

The Psychology

We found that while a cat door into the truck camper wheel well seemed like a great idea to us, for some reason, Ithmah didn’t initially cotton to it. We laid the brand-new, freshly filled litter box in the wheel well area just inside the new cat door, and made coaxing noises to the cat. Ears went back, and suspicious looks were the order of the day. After several attempts, we took the bull by the horns and stuffed the reluctant feline through the new portal. A gray streak shot back out of the cat flap, and the suspicious looks turned rather murderous.

It’s really amazing how long a cat can keep her legs crossed. We finally relented and kept the original access door open. After holding out as long as she could, Ithmah crept into the new powder room, took care of business, and flew back into the camper. Finally, after a few trepidatious trips to the loo, her nibs was induced to use the cat door. Since that time, it’s been a lot easier on all of us.

It may take a little bit of work to adjust your pet to the new idea. In our case, it seems the confined, dark wheel wells were the problem, not so much the actual pet door. In the travel trailer setup, the fractious feline often vanishes from the trailer and hangs out in the storage compartment-cum-throne room.


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Hi, I’m writing a blog post about ideas for hiding a litter box in an RV, and I was wondering if it would be okay if I used your photo above on my blog with a credit to your name a link back to your website or preferred URL?

Thank you!

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So what do you while you are on the road with your cat? Do you keep a litter box in your truck?