Summer in Japan is characterized by hot, humid weather that continues from the rainy season (tsuyu), which starts around June. Separate from measures against winter condensation and mold, summer calls for making good use of your air conditioner's dehumidifying function and keeping up habits that prevent insects from appearing. Here, we'll go over the basics of managing summer humidity and dealing with the insects that commonly show up in homes. We cover winter condensation and mold measures in more detail in a separate article. The period around the end of the rainy season, in particular, tends to bring both high humidity and high temperatures together, making it an especially uncomfortable stretch.
- Unlike winter, both temperature and humidity are high from the rainy season through summer, so dehumidifying-focused measures are effective.
- Using your air conditioner's dehumidify (dry) function can sometimes keep humidity more comfortable than the cooling function does.
- Tears in window screens, grime in drains, and gaps around window sashes are common causes of insects getting in.
- Sealing food waste and throwing it out promptly is the basic way to prevent insects and odors.
- Placing a dehumidifying agent or insect repellent in storage spaces is another effective measure to combine with the rest.
The Characteristics of Japan's Summer Climate
Summer in Japan can be divided into the rainy season, running roughly from June to July, and the hot, humid period that follows. Days with humidity above 70% aren't unusual, calling for a different kind of home care than the dry cold of winter. While measures against winter condensation and mold are about being mindful of temperature differences, summer measures center on dealing with high humidity itself. The timing of the rainy season's start and end varies by region, but it's worth being especially mindful of humidity control from June through July.
Making Use of Your Air Conditioner's Dehumidify (Dry) Function
The basic approach to managing summer humidity is using your air conditioner's dehumidify (dry) function regularly. Even on days when the temperature isn't especially high, high humidity can still feel uncomfortable, so the dehumidify setting can sometimes be more comfortable than cooling. Using a dehumidifier alongside it is also effective when drying laundry indoors. Combining this with a fan or circulator helps efficiently distribute the dehumidified air throughout the room.
Places Where Insects Tend to Appear, and How to Deal With Them
Hot, humid conditions are also the kind of environment where dust mites, cockroaches, and small flies tend to appear. Kitchen food waste, grime in drains, and damp cloth items are all places insects are drawn to. Put food waste in a container or bag that seals tightly, and avoid letting it pile up until the next trash collection day. We cover the basic rules for taking out the trash in a separate article. Water pooling in the saucer under a houseplant, and the area around the drain trap under a sink, are also easily overlooked spots where insects tend to appear. Tatami and carpet trap moisture and dust easily, creating an environment where dust mites can multiply, so vacuuming regularly is effective there as well.
Caring for Window Screens and Drains
When you open a window to let air through, check the screen for any tears or gaps first. Insects can get in even through a small gap. Cleaning the drains in the kitchen and bathroom regularly also helps curb slime and odors from developing, making them less attractive to insects. Dust and sand can build up on the sash rail and keep the screen from sliding smoothly, so it's worth cleaning that area at the same time.
Using Dehumidifying Agents and Insect Repellents
Placing dehumidifying agents and insect repellents in poorly ventilated storage spaces like closets and oshiire is also effective. Store-bought products come in a wide variety, so it's worth choosing between freestanding or hanging types to fit the shape of your storage space. Don't forget to check the replacement schedule regularly, either. Some clothing insect repellents have a fairly strong scent depending on the type, so be mindful of how much you use and where you place them.
Frequently Asked Questions
Can I use the same humidity measures in summer as I do for winter condensation?
The underlying idea overlaps in some ways, but since summer measures center on dealing with hot, humid conditions themselves, summer-specific approaches like using the dehumidify function are also needed.
Why do insects still get in even though I have window screens?
They may be getting in through a small tear in the screen, or through a gap between the window and the sash. Check regularly, and repair any tears you find.
What should I do if I'm concerned about odors or insects from food waste?
The basic measure is to use a container or bag that seals tightly, and avoid letting it pile up until the next trash collection day.
Summary
Because summer in Japan is hot and humid, it calls for humidity and insect measures different from those used in winter. Building daily habits like using your air conditioner's dehumidify function, cleaning regularly, and managing food waste lets you get through summer comfortably. Keeping up seasonal care like this makes it easier to maintain a comfortable living environment all year round. If insects keep appearing despite these steps, it's also worth considering store-bought pest control products.