Dealing With Mold In Japan During The Rainy Season

Tokyo has no shortage of rain during the 梅雨 (rainy season) and with the additional rain comes an additional problem. Warmth, humidity and poor ventilation combine to form a summer long battle with カビ (mold).

Most Japanese households are armed with tools and tricks to stave off the humidity and prevent moisture problems before they strike. However, without centralized air units, it is difficult to control the fluctuating humidity and temperatures during the rainy season.

Fortunately, dehumidifying options that are electricity free and easy to find at a local supermarkets are abundant. Let’s talk about Japan’s best kept secret: 除湿剤じょしつざい (dehumidifying agents).

Dealing With Mold In Japan During The Rainy Season
Dehumidifying Agent

Popular brands such as, ドライペット, 水とりぞうさん and ドライウェル produce a large variety of cost-effective dehumidifying products for use in the home. Most Japanese homes have at least one or two items from these brands tucked away.

Desiccant pack in Japan

Dealing With Mold In Japan During The Rainy Season
Desiccant Pack

Most people are familiar with the desiccant packs (乾燥剤かんそうざいパック) found in new shoes, dried goods and shipped furniture. These packets are easy to identify with their large (Do Not Eat) labels.

While most of us casually toss these packs into the garbage, Japan has made desiccant packs a convenient way to prevent mold during summer months. It is easy to protect folded clothes from mold growth by adding a few desiccant packs inside a wardrobe.

Over time the packs expand in size, absorbing humidity and reducing moisture levels in shelves and drawers.

Recommended Usage: It’s recommended that these be replaced every 1-2 months and to be kept for a maximum of 6 months.

Humidity moisture containers in Japan

Dealing With Mold In Japan During The Rainy Season
Humidity moisture containers

The design of this product is quite simple but ingenious. It traps moisture from the air and the collected moisture pools at the bottom of the container. Over a month it becomes easy to see how much moisture your home has accumulated.

Unfortunately, this product is not recommended for large open spaces. It is simply to small to be effective in open rooms but they are perfect for placing in closets, shelves and compact spaces.

Recommended Usage: It is recommended that these be replaced after 1 month but this time could be sooner depending on the season.

Absorption pads in Japan

Dealing With Mold In Japan During The Rainy Season
Absorption pads

Protecting fabric-based objects extends beyond the closet. Whether you’re using a futon, sofa or bed, absorption pads will help reduce the sweat and moisture in contact with valuable furniture.
These sheets (湿気取しっけとりシート) are available in a variety of shapes but are easily recognizable from their baby blue color. A special sensor lets you know if the sheet has absorbed moisture by changing from blue to pink.

Recommended Usage: Simply place the sheet outside in the sun for 2-3 hours to reset the moisture sensor.

Air circulation

With mold, the best offense is a good defense so preparing for the rainy season starts today. Luckily, it is easy to find affordable solutions to deter mold growth.

For those with poor in-home  circulation, many air conditioning units offer a drying function. Using this function sparingly, along with dehumidifying agents may be the perfect solution to keep moisture levels in the home low. Outside of these tips, we recommend opening windows on sunny days to promote natural air circulation.

Recommended Usage: The sun and a nice breeze are the best allies when it comes to fighting mold in a Japanese home. Best of all, it’s free!

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