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Installing a cat door fixed my home office

Installing a cat door fixed my home office

Working from home with a cat. I want to work quietly, and there is a small daily battle instead.

Once home is also the office, every sound and every condition in the house lands directly on your work. Anyone with a cat will recognize the specific problem: the negotiation with an animal who wants into the room you are working in.

Originally published in Japanese on November 19, 2025. This English version was written in September 2026.

He calls at the door mid-task. I open it, he walks in satisfied, and shortly afterwards he wants out again and asks to be let back in.

Leaving the door open solves that and wrecks the room temperature. Closing it annoys the cat. There did not seem to be a third option.

There was. I fitted a cat flap — a pet door — into the office door. It cut stress for both of us, and my main feeling now is that I should have done it much sooner.

The problem: a cat who wants in, and also out

Cats do as they please. Why he wants in, and why he then wants out, is known only to him.

My cat sitting in the home office

Meanwhile I am in a meeting, or concentrating, or deep in a piece of writing. None of this registers with him as a reason to wait.

Let me in.
Actually, out.
In again.

This runs well past a few times a day. He is charming enough that I always give in, and my work suffers for it.

The cat waiting outside the closed office door

Leaving the door open costs heating and cooling. Cool air escapes in summer, warmth disappears in winter, and an unstable room temperature makes it harder to concentrate.

An open door also brings the rest of the house’s noise in.

Closed, the cat protests. Sustained complaint gets the door opened eventually.

What I fitted

I went looking for something I could install myself, and picked a basic flap-type cat door with:

  • DIY installation
  • An opening sized for a cat to pass through comfortably
  • A flap that swings on a magnet, so it closes itself
  • A four-way lock for restricting passage during meetings or while out
  • A plain appearance

To be precise about that third point, since “automatic” would give the wrong impression: there is no motor and no electronics. The cat pushes the flap open with his head, and a magnet at the bottom pulls it shut behind him.

The price settled it — around 1,200 yen, roughly US$8 at September 2026 rates. This is the cheap end of the category, and it is a simple mechanical part, so the low price is not really a compromise.

Installing it

This type is fitted by cutting the hole in your door yourself.

The cat door kit and instructions before installation

Worth saying before anything else: this permanently modifies a door. If you rent, that is a conversation with your landlord, not a weekend project. It is also worth knowing what your door is made of — a hollow-core internal door behaves very differently under a saw than a solid one.

The instructions include a template. Cut it out to size and draw the cutting line onto the door.

The cutting line marked out on the office door

Cut along the line, then fix the plates through the door from both faces with screws.

Cutting a hole in a door makes you careful, so it takes a while. I would say it should. You also need a tool capable of making the cut, which is worth thinking about before you buy the flap rather than after.

The cat flap fitted into the door

The mechanism is simple: the cat pushes and the flap opens. The magnet underneath means it does not sit open.

There is a click as the magnet catches on closing, but brushes around the flap keep it quiet enough not to bother me — and I notice noise while working.

The lock is the part I appreciate most. Four settings:

  • Fully locked
  • Out only
  • In only
  • Both ways

Switching between them takes a second, which is all you need when a meeting is about to start.

The cat took two days

The important review is his.

The clear flap confused him initially. He stood on the far side of it and complained at me through it.

On day one he needed me to hold it open. On day two he was pushing through by himself. After that it was simply his door.

The cat coming through the fitted cat door on his own

Being able to come and go as he likes suits him. The in-and-out demands have stopped, so I can concentrate.

When I lock it for a meeting he does petition me through the clear panel — but the video call cameo, endearing as it is, no longer happens.

The heating and cooling was the real win

The change I noticed most was not the cat. It was the room temperature.

Through the period of leaving the door open, cooling struggled, heat escaped, and the air conditioner ran flat out. Hot in summer, cold in winter, expensively.

With the flap in, the door stays properly shut and only the cat passes through, so the temperature barely moves.

Summer cool and winter warmth stay in the room. That alone made the workspace dramatically more comfortable.

I did not measure the electricity, so I cannot give you a figure — but a small unheated office in a Japanese winter is not a subtle experience, and it stopped.

Worth doing

Since fitting it, the small stresses during work have largely gone. The temperature holds. The cat moves freely and is pleased about it.

The finished cat door installed in the home office door

Working from home got measurably better for something under two thousand yen and an afternoon.

Three problems, one part:

  • The cat calling at the door
  • The temperature collapsing because the door is open
  • The mid-meeting entrance

If you work from home and live with a cat, this is the cheapest improvement to your working conditions I know of — provided the door is yours to cut.

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These notes come from running this setup daily.

About the author

Hidekazu Ishikawa

Hidekazu Ishikawa builds and runs web products with AI agents from Japan. Available for consulting on AI workflow design and web development.

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