what to do if you find cockroaches or mold in your Japanese apartment

Author: J.J.

Two Nuisances You Might Find in Your Japanese Apartment

Apartments in Japan are the biggest challenge you will face. There are so many things to know and do that you could write an entire book about the trials and tribulations of apartment hunting alone. While the process may be difficult, once you do find a place and go through the paperwork it is all smooth sailing.

But smooth sailing does come with a few waves. Things break down and the unexpected have a tendency to creep up on you. It is best to be prepared for when things get out of hand. Here are two rare problems that I’ve overcome in my Japanese apartments.


Spring brings many great things: going to the beach, cherry blossom viewing parties, and mosquitoes. Okay, maybe the last one is not a “great thing” but spring is representative of life. Every insect comes out of hiding to look for food and a place to settle down. Of all the insects to face, the number one biggest insect you don’t want to see in your apartment is the cockroach.

Now, I will preface this by saying that cockroaches are a rare sighting: most reside in the lower half of Japan and only come out of their murky shadows to hunt for food scraps. A sign that you might be bunking with the brown insects is rustling at night. From sundown to sunrise they scavenge. If you flick on a light in your bathroom or kitchen and hear scurrying then you have a problem.

The first thing to assess is where they are coming from: cockroaches don’t live in your room but travel through the cracks and holes of the building. If you can find and patch their entrance then you’ve eliminated the problem. It’s best to tell your apartment’s management company or landlord what is going on. They will sometimes help you with manpower and supplies.

Gokijet ( ゴキジェット, gokijetto) spray

Gokijet ( ゴキジェット, gokijetto) spray

If you can’t patch the hole(s), Japanese have an assortment of other tools to defeat these miniature menaces. My recommendation for going toe-to-toe (I’m pretty sure they don’t have toes, but it’s a saying) is a one-two punch of Gokijet spray and Black Cap capsules.

Place the Black Cap capsules around the area that gets the most insect foot traffic. The capsules contain poisoned bait that they will eat and scurry home… never to be seen again. The spray is an offensive tool that deals the deathblow to a sprayed insect and wards off the other bugs. Use these two and within a couple of weeks you will never see a cockroach in your place again.


A wall of rain

A wall of rain

It rains in Japan. It rains a great deal in Japan. I wrote a whole article on what to do when it rains in Japan, while it was raining! Most people have named it the fifth season, the rainy season, that comes around late May to early July. Then there is typhoon season, that peaks around August/September. While the rain is very on-again off-again, it does produce a very humid environment. Which mold loves.

Mold grows in dark, damp, stagnant air places like under your sink, or in the rainy times of the year, your whole apartment. You can tell when mold is growing because it produces a certain musty smell.

Depending on the type of mold it might have a fuzzy white, green, or black appearance. Mold eats organic material so it will grow on wooden furniture like bookshelves, doors, and beds, as well as cotton-based material like clothes and sheets.

White Vinegar, a natural alternative for bleach

White Vinegar, a natural alternative for bleach

There are many routes to tackling this nuisance, but this fight is more of an uphill battle. Mold is a constantly regenerating organism: a small colony of mold can ride on the wind and multiply, producing a kingdom of problems for you.

So here is a list of steps you can take to fight off mold. Try starting them all at the same time for the best results:

  • Keep your windows and balcony doors closed during the summer, use air conditioning
  • Scrub the places where mold is growing, or will probably grow, with white vinegar (You can find white vinegar in a glass bottle at Kaldi’s)
  • Clean and wash down your closet. Then wash all your clothes, throw in a little white vinegar into the load to be on the safe side
  • Sun dry clothes and hats: the sun’s ultraviolet radiation is said to kill mold
  • For porous wood furniture, like bookshelves and beds, scrub with a mixture of borax and water, water loosens the mold and borax will kill it and prevent it from re-entering the surface
  • Open your windows during the colder, dry months, this will break the stagnant air and drop the temperature of your apartment
  • Invest in a digital hygrometer, also known as a digital humidity monitor; mold tends to grow when indoor humidity exceeds 60%

If the situation worsens or you see black mold, immediately contact your apartment management company. Work with them to schedule a meeting with a professional to access the situation.

Sometimes all it takes is a little extra cleaning one day or running to the dry cleaners to save you frustration later on. Maybe you won’t ever see a single cockroach or colony of mold while you live here in Japan, which is great! But it is best to know the signs and take measures to prevent the problems from occurring. So keep your place tidy, cool, and dry and you will have a great time living in the Land of the Rising Sun!

By J.J.
Software Engineer and Blogger at TalentHub
Usually coding, writing, or exploring Japan.

?Read more TalentHub blogs: https://talenthub.jp/blog/?lang=en

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