If you’re not following along on Instagram, then you might not know that we have cats! Yes, like so many other people in the midst of a pandemic-induced lockdown, we decided to get a pet. But of course, this wasn’t a spur-of-the-moment decision. Richard and I have always wanted pets. We’ve been planning on adopting cats once we moved out of the flat and into someplace with a yard.


When the first lockdown hit, we started to seriously talk about getting cats. We’d always figured we would adopt a couple of older cats but had intended to wait until the major building work was finished. But after being stuck at home every day, we started really wishing we had something furry to love and care for. I found myself surfing rescue sites in the evenings, but none of the centers were open to allow adoptions. And that’s when it hit me… kittens!

See cats don’t understand things like lockdown. They’re still out there, getting preggers and having kittens. I figured there might be some in our area needing a new home. I’ve always wanted to have kittens, but since we both work 9-5, we wouldn’t be around enough to look after them. But hey, now we’re stuck at home all day every day!! Suddenly this lockdown has an upside – we could get kittens!

So we looked around in our area and sure enough, there were some Maine Coon cross kittens available nearby! I’ve always been of the opinion that the larger and fluffier the animal, the better… so a kitten with even a hint of Maine Coon was right up my alley! (Not sure what I’m talking about? Just google Maine Coon and you’ll see!)

Enter the cutest little fluffballs you ever see… Moose and Smudge!

I can’t handle the cuteness…

They really made lockdown just the absolute best. I still find myself looking back at photos and videos from when they were wee little things and it makes me want to get more kittens aaaaaall over again. (Richard keeps saying no.)

Moose and Smudge | Hello Victoria

So cute!

Anyways, what was this post meant to be about again? Ahh, right. My secret cat door.

The plan

I don’t know about you, but I’m not really a big fan of the way most cat/dog products look. Who decided that brightly colored plastic everything was the way to go? If it’s going to be on display all the time, it could at least look nice.

So now that the cats are getting a bit older, we have been talking about where their litter tray will live. It lives in the living room at the moment, where we shut the cats in each night so they don’t get into mischief. But eventually, we’re planning on moving it to our under-stairs cupboard.

DIY secret cat door | Hello Victoria

The only problem with that is how do they open the door?

We obviously can’t leave it open all the time, but traditional cat flaps just look so… bleh. I wanted better for myself my kittens (yes, I still call them kittens).

So I looked online at some tutorials where people converted one of the panels on a paneled door into a hidden cat flap. They all used really clunky mechanisms, so I tried to come up with something hidden. My idea was to install some small metal rods into the sides of the door and then router a groove/track into the sides of the panel that they could slot into. Then, in theory, the panel would just swing on the rods.

Oh, and apologies up front for the lack of progress photos, or just good photos in general. Most of these are crappy iPhone pics, as I was sort of making it up as I went along.

Turning plain into the paneled door

The door in question was actually not a paneled door to begin with. It was clearly not the original door, but something they must have swapped in at some point over the years. Because it wasn’t as thick as a normal door (only 18mm), I knew that I could add thick MDF pieces to the face of it. That would create the four-panel look, without adding too much weight/depth. I based the dimensions of the panels on the original doors with have in the house, scaled down appropriately to our smaller cupboard door, and cut them out of 12mm MDF.

DIY secret cat door | Hello Victoria

Before they all got nailed into place, I marked the inside of my secret door and cut the panel out. I had to drill two holes in the corner to get the jigsaw in, but I knew I could fix that later with wood filler. Once the panel was out, the MDF got wood glued and nailed in place. I could go into detail about filling/sanding/painting the door, but I think that’s all pretty self-explanatory.

DIY secret cat door | Hello Victoria

Secret door mechanism

I picked up a length of 6mm steel rod at B&Q to inset into the door frame and finally plucked up the courage to learn how to use a router. Luckily, my router bit set had a straight bit that was 6.35mm in diameter. I figured that if I routered a track using that bit, the rod would perfectly slot in with just enough wiggle room to swing about.

Using an angle grinder, I cut two lengths of the steel rod, 20mm long. I thought that I could drill into the door 10mm, leaving 10mm exposed for the door to swing on. There was no real science to the height that I chose for the rods to be installed. I just eyeballed it to where it made sense in terms of gravity allowing the door to hang mostly vertical when not in use. For my actual panel which is 535mm tall, that ended up being 95mm from the top.

DIY secret cat door | Hello Victoria

I measured the door frame first, marking the same distance down from the top on both sides (95mm), in the middle of the original door frame (not including the added MDF). Using a 6mm wood drill bit (in a right angle drill attachment since the opening was too narrow), I drilled 10mm in for each rod. A bit of glue in each hole and they got hammered into place.

Next up, I needed to router a track to allow my door to slot in and then hang. Basically, I drew a hockey stick shape (see below), 6mm wide, so that the rods could enter from the back of the secret door and then slide up. The stopping point had to be exactly level with the top of the rods, otherwise, my door wouldn’t line up. I did it in a couple passes of the router, being careful not to go past the top mark. If the sides were a bit wonky, no big deal, but the top line really mattered.

DIY secret cat door | Hello Victoria

And it worked! Well, mostly.

There’s always going to be a bit of sanding required to make it swing perfectly without catching. And the thickness of your panel will make a big difference. Since my door wasn’t a normal four-panel, the swinging part was actually a lot thicker/heavier. So I ended up sort of rounding the back edges, top and bottom, to allow for a perfect swing.

Finishing touches

Now that it worked, I just had to make it look pretty! I purchased some ogee panel trim at Wickes to match our existing four-panel doors, and installed it around the inside of each normal panel, with glue and some veneer pins. For the swinging door, the trim was installed on the actual panel, not the door.

DIY secret cat door | Hello Victoria
The original door is on the left, new trim is on the right.

Nail heads were sunk, everything got filled and sanded, and then it was paint time! I painted the door in a custom color (which we dubbed “‘Bout Ye”), like all the trim. I couldn’t find a dark green that I liked, so we color-matched it from a mixture of F&B ‘Bancha’ and F&B ‘Pitch Black’.

DIY secret cat door | Hello Victoria

The swinging panel had to undergo a few more rounds of sanding once the door frame had its final coat. With the clearance for the swing only a couple millimeters, layers of paint can get in the way. I just had to keep testing it, sanding it back, painting… and then testing again.

The final result!

Add a shiny new beehive knob and boom! Secret four-panel cat door.

DIY secret cat door | Hello Victoria

Part of why I think this works so well is that the panels naturally have a shadow all the way around due to the trim. So if there’s a subtle gap all the way around one panel it blends in. It would look even better on a proper four-panel door, where both sides have panels. The inside of this door is flat, which means that you can see it from the inside. However, it’s not as clunky as some of the mechanisms out there, so I’ll let it slide.

DIY secret cat door | Hello Victoria

I also just had a lightbulb moment where I realized I should have routed from the bottom straight up the side to my stopping point. You could slot it in that way and never see where it goes in! If anyone attempts this, do that!

The only niggling detail is that I’d like to sink a couple magnets into the bottom edge of the panel/door. Right now, if you open the door, the panel starts to swing. It would also help the panel stay perfectly vertical all the time. I know I have some perfect neodymium magnets somewhere in the house, so I’ll add them once I find where they’re hiding.

DIY secret cat door | Hello Victoria

But hey, it works! And it’s a far cry better than what was there before, don’t you think? Do you feel like attempting your own hidden cat door? Or am I the only crazy one…

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