Outdoor Cat Shelter
2025-11-23 10:49 - Making
I just posted about my stray cat friend Marmalade. It's getting to be winter time and it's really too bad Marmalade has to stay outside in the cold. People sometimes make little shelters, a cathouse, for outdoor cats to stay in over the winter. Last trash day some across-the-street neighbors were throwing out a ruined old chest of drawers. I snagged it to be raw material for making one of my own.
The most common design seems to be based around a plastic storage container. When looking for more inspiration I found a commercial product, the Feralvilla and I like its design. The bottom-entry seems like it will do a great job keeping out the worst of the wind. Of course, using salvaged material means I have to tweak the design to work with what I've got. It's all particleboard, but the top and sides are ⅝" material.
So here's my design. The Feralvilla's walls go all the way to the ground, with entries cut out and a wind baffle. My material isn't big enough for that, so I put a wind baffle "hallway" inside. All the walls and floor are the mentioned boards. The roof is a frame of 2x2 with two layers of the thin hardboard backer from the drawers. I started breaking down the chest of drawers and coming up with this design Sunday night, and finished that Monday morning, and started building.
The first and second day saw much of the main structure cut and rough assembled, with screws (also salvaged!). You can see that I'm doing my best to cut-to-size, rather than to plan, with the angled sides. They're fit with the screws so I can see how big they really need to be, possibly accounting for minor errors in the other pieces. I'm also using the table and some shims (cut for this purpose) as clamps: this is wider than my 12 inch F clamps. Happily, I got the dado (cut with a router) to line up great, for fitting the "hallway" wall inside. One piece of it is floating in the slot here, to confirm.
Next on Wednesday I finalized the main structure, mostly cutting the sides to the proper size. Some aggressive sanding and "glue and sawdust" wood filler got those in place pretty well, and things got glued together. Screws functioned as clamps here. Then I got the first part of the roof assembled: Some 2x4s were cut down to 2x2 and half-lapped, then glued to the first layer of ⅛" hardboard. A clamp at each corner and the middle of each long side did great here.
With the rest of Wednesday and most of Thursday I painted. And painted and painted. Being particleboard, the paint is extra important for weatherproofing. I got five thin layers or so on everything, though I didn't keep count carefully. With the paint dry I started insulating. About the cheapest material I could find was also pretty perfect: ¾" foam boards, precut for 16 inch stud bays, and I needed 13 to 15 inch widths. For this I threw together a hot wire cutter. (I had the wire originally for the plastic bending part of the power supply project, in the back of this picture powering the cutter!) The hot wire goes through the foam quick, and especially important leaves a clean edge without bits going everywhere.
Now we're on to Friday. The main structure is mostly done and I'm finishing the roof. I had the material so I put two layers of insulation on the roof: one inside plus one outside between the two ⅛" structural layers. This came out pleasantly strong; especially because it only needs to hold itself up. For the main structure I let the walls' insulation come ⅛" up above them, with the inner foam layer on the roof this should form a decent seal. Here again, some foam pieces are left rough cut, trimmed to fit after assembly is complete. These layers were all glued together, and you can see traditional clamps working together with gravity clamps in this setup.
Also on Friday, here you can see the main structure, finished. Look closely and you'll notice the main floor on the right, with entry hole. On the left you can't see a layer of insulation on the floor, beneath another ⅛" hardboard layer protecting that. All the joints are caulked for air sealing (plus to help hold the insulation in place). A second view reveals the "hallway" and doorway.
Saturday saw final assembly of the roof. First the whole thing was wrapped in a layer of tar paper. I ended up leaving this exposed down the edges of the roof panel. The shingles and tar paper are also both salvaged, this time from the shed. The shingles have a proper starter course, and then are stapled (where covered) and glued (with more caulk) down onto the tar paper, also glued onto the roof. Unfortunately the shingles were only barely wider than the roof itself so I couldn't stagger the joints very much. There's never fewer than two layers anywhere though, so it would probably still be fine even if the joints in the tabs were all aligned.
And finally here it is, installed on the porch. This is where Marmalade has been having breakfast for some time. With the bottom entry, it looks quite unassuming: just flat white walls on all sides. (The exterior paint was also salvaged. Bright white wouldn't be my first choice, but that's the only exterior paint that was freely available.) All the roof joints are caulked. It's hard to tell in this picture, but they are properly lapping so that water shouldn't run in anyway, but extra sealant can't hurt.
Only time will tell if Marmalade will figure out that there's a nice insulated bedroom to hang out in now! The bedroom ended up around 13x18 inches, and over 12 inches tall at the lowest side. Pretty close to ideal size for a single cat. A small insulated space can be warmed by the cat's own body heat. Not pictured: there's a layer of straw bedding on the floor there. Research strongly suggested straw as the only/best option here. I couldn't find any for a while, but then discovered that Tractor Supply had some nearby and in stock.
