What on earth is a catio, you ask? A catio is a safe place for indoor cats to go outside, usually built on a patio. And yes, you call it a catio because a cat house has a whole ‘nother meaning. That means, it needs to have screened windows for ventilation, and be safe to keep the cats in and other animals out.

We needed to build a catio because we want to sell our house, which meant getting the cats outside.

My first thought was to scour the internet for easy plans on making one. So I figured if I could find really good plans that weren’t too difficult, I’d be happy to build something. I needed something that would be light enough that when we move I could have a couple guys lift it into the back of a friend’s pick up truck and take with us. But all the plans on the internet either cost a lot or were really complicated. I tried writing my own plans, but then popped something in my elbow and the idea of doing a lot of manual labor myself went out the window. We tried three different handymen and all three turned us down. I’m not counting the 4th who didn’t even respond. Sigh.

I needed an alternative. I looked at modifying chicken coops (some of these could have possibly worked, so if this catio idea doesn’t work for you, consider chicken coops from someplace like wayfair.com). I looked at modifying dog houses, sheds (ridiculously expensive), and even children’s play houses. Nothing really worked for what I wanted – something that was big enough for me to easily get inside to clean and that would hold a good-sized cat tree, was light enough to move, but also didn’t cost more than about $500.

Finally, I started looking at greenhouses. The problem with a greenhouse, though, is that they’re designed to keep heat in during cold weather and allow lots and lots of sunlight in. Great for plants, not so great when you want it for cats in Tennessee heat.

What I found was a Palram Greenhouse. It’s available at several stores, but I ordered from Amazon. To be specific, it’s a Palram Nature Series Hybrid Hobby Greenhouse – 6 x 4 x 7 Silver. Aside from the fact that the instructions are TERRIBLE, I’ve been pretty happy with this. It’s surprisingly sturdy and well-made and light. It weighs less than 70lbs. So it’s awkward, but easy for two adults to lift. It was also fairly easy to modify to create a catio.

Make sure you give the catio a good floor. Ideally, you’ll have a floor wider than the catio. Then be sure you attach the catio to the floor. Make sure the floor is raised so that water won’t pool under it. I used two sheets of 4×4 sanded plywood on top of patio pavers. I couldn’t fit anything bigger in the back of my car. Right now, it’s held down by bungees. If this were going to be stand-alone away from the house, I’d bolt it down. But since this is protected by the deck above, it doesn’t get a a ton of wind.

Two problems to solve when modifying a greenhouse to a catio:

Problem #1 – too much sun. I solved this by the fact that I built it underneath our deck. It will be in shade most of the time. However, I added a curtain on the inside that I can use to block even more sun. They do sell netting for these, so if you don’t have a deck above it, check that out. The cats are enjoying the curtain, though, because it just makes one more place for privacy. They tend to each stay on opposite sides of it.

Problem #2 – no ventilation. This was the most difficult problem to solve.

• Buy 1/4″ metal rods (2 per panel, total of 6)  – Note, I tried bamboo first and it broke.
• Buy heavy gauge thread for outdoor use
• Buy a roll of pet safe window screen, 48″ wide, 96″ long

Step 1: During the building step where you insert the wall panels, don’t install three of the wall panels. Just a hint, make sure you leave two solid walls on opposite sides and make sure the panels you remove have the metal angle brace. That makes it much sturdier than if you remove too many panels or remove ones that the original walls are the primary support. I did one open panel on the front next to the door and two panels on the rear wall. Keep the side panels as-is since those do not have metal bracers to help with keeping it sturdy.

Step 2: Using a sewing machine, make pockets for the rods on the 3 panels that you measure to fit, then insert the rods. You don’t have to worry about tops and bottoms of the screens.

Step 3: Insert the screen into the metal upright pieces where the wall panels would go. Use the included tool for your greenhouse to bend down the extra few inches of rod you don’t need. (If I had a way to cut the rod, that would have been better, but I wasn’t willing to buy a tool for that).

Step 4: Continue building the greenhouse following regular directions. Make sure when putting the upper cross braces in, that you tighten it through the top of the screen to hold it.

Step 5: After the greenhouse is built, use thin metal wire to thread through the bottom of the screen and attach the bottom to the greenhouse. Note: I left a couple gaps where I could put outdoor extension cords through so the cats could have their water fountain and, where in the summer, I could put a fan inside, if needed. Warning, I’m not very happy with the amount of wire this exposes to the cats. So I’ve used blankets and other items to cover the wire up so the cats don’t play with it. I may try to come up with a better solution for this in the future. It’s possible using the thread could work, but I felt like the wire held it more sturdily.

After this, I moved in their cat tree, litter, water, food and some blankets. The cats love it.

Final thoughts:

What I’d do differently if I could: I’d get a larger greenhouse. 4×6 sounds pretty large, but it really isn’t. I’d love to have gone with the 8×8 version. However, that would not have fit in the space I had or been easy to move. On the whole, I’m very happy with how this turned out.

What about rain? After these pictures were taken, I used two of the spare panels with some wood to create an overhang next to the wall of the catio on each side where the plywood extends. This will help prevent rain from pooling on that wood and getting inside. In the event of a big storm, I plan on using the panels almost as storm shutters and propping them up from the inside. And, of course, I will bring the cats inside.

Talk to your vet. We did talk to our vet before doing this. Our cats are now on flea/tick medicine because, even though this is screened, mosquitoes and other bugs can still get to them.