Can Hot Water Kill Cockroaches?

Boiling water can burn cockroaches to death on contact. Drowning roaches in any liquid above 130°F will kill them instantly because they must remain moist to survive. Water boils at 212°F, and those bugs are not tough enough to survive that heat.

When roaches are dipped and left to soak in hot water at 100°C, their bodies are dissolved after 15-30 minutes. They have soft body that is full of fluids. Hot water removes moisture from their external cells, thus leaving them exposed to severe burns.

High temperature in water molecules is what kills them. Since roaches cannot survive heat, any hot liquid above 125°F can terminate them. However, warm water below 95°F can harm them, but they may survive depending on how long they are exposed to it.

Can Hot Water Kill Cockroaches?
Hot water for cockroaches

Does hot water kill cockroach eggs?

Soaking cockroach eggs in boiling water at 180°F for 20 minutes or more will kill them. Hot water also destroys the sticky liquid that glues them to any surface. Roach eggs cannot survive constant temperatures of 150°F and above.

Roach eggs have a tough casing that can resist heat and must be exposed to high temperatures for a long period. The constant heat will affect the eggs when soaked in hot water. After 10-15 minutes, they are dissolved and destroyed.

In this case, the heat is used to kill roach egg contents. Water at room temperature cannot kill roach eggs even if you soak them for a day in it. However, freezing them below 32°F for prolonged hours can stop the cells from multiplying and growing.

Hot water can also be flushed down the drain to kill roach eggs glued to the pipes. For great results, you can mix it with dawn dish soap. Soapy water kills roaches, while hot water helps in destroying the egg contents as they are washed down the drain. Baby roaches are then left with no chance of crawling into your house.

How to kill cockroaches with hot water

To get rid of roaches hiding in clothes, wash them at 55°C for 30-60 minutes. However, this depends on the type of clothes being washed. Some fabrics can be destroyed at high temperatures, so check the labels’ washing instructions.

Add a gentle detergent that helps kill roaches and their eggs once they break open from machine spins. Remember to check the detergent’s strength. Use it in small bits if it is too strong since extra hot water combined with strong detergents can easily destroy your clothes.

Washing your child’s backpack in hot water can kill roaches and their eggs. However, check the amount of heat the backpack can take on the washing instruction label. You may either deep and soak it in hot water for 30 minutes without detergent or use a washing machine.

Hot water can easily remove the original colour from a backpack; you must be careful before washing or soaking it. Bugs hide in children’s packs. That is how roaches get in cars from the house. Kids can also carry roaches from school to your home in their bags if their friends come from infested areas.  

Spraying bleach and hot water

Mixing hot water and bleach kills cockroaches by burning and dissolving their body cells. Bleach and hot water in equal proportions and douse them with it. As long as they are well soaked in the solution, they will die. Have them drowned in the solution if you want them dead instantly.

This can also be flushed down the kitchen sinks to kill roaches that hide in there. If you have an infestation in the drains, repeat this twice a day (morning and evening). Flushing 2 cups of bleach and the same amount of boiled water should be enough for the job.

However, pure bleach should not be flushed down the drain since it can cause dangerous chemical reactions. This can also destroy the drainage pipes and lead to unwanted leakages. When pure bleach kills cockroaches in a drain, flush distilled water afterwards to reduce the reaction effects.  

When using this for roaches in bed and mattress, test first to see if it is causing discolouration. A test can be done by spraying a small area to see if there is any reaction on the surface. Even if there is none, use it in small portions and confirm that there is a good contact.


Steam cleaners are designed to release boiled water in the form of steam. This comes with enough pressure to penetrate fabrics and kill any hiding roach. The pressure produced from a steamer is enough to harm roaches in carpets or any surface it is used on.

The pressurized steam can also help get rid of cockroach eggs, but it will not kill them. Soak roach eggs in vinegar and equal parts of hot water for 15 minutes or more if you want them dead. Steamers can help remove them on any surface they are glued on.

Steam cleaners can also remove cockroaches on patios and wooden floors. However, do not use a steamer on unfinished wooden floors. The head can damage unsealed wood, and using it frequently on those can reduce its durability.

Additionally, rubbing alcohol for roaches can be mixed with hot water equally. This reduces the negative effects of the solution on any surface. However, it should never e left to sock anywhere. Simply spray it directly on the roaches.

Do cockroaches drown in hot water?

Cockroaches drown in hot water because no surface tension keeps them floating. They will also be burnt and dissolved when submerged in hot water. To kill them instantly, spray or drown them in 1 cup of dawn dish soap mixed with 0.5 gallons of hot water.

Dawn dish soap is a common household product that can kill roaches if dipped. For it to be effective, mix it with hot water. While dawn blocks and chokes roach to death, hot water will burn and increase fatalities. Salt can also kill roaches; adding 1-2 tablespoon is a good idea.

Boiled water and soap can break the surface tension, making roaches sink and drown. Any hot water heated above 120°F is enough to kill roaches when using dawn. Hot water will also help push soap into the tiny breathing holes on a roach’s abdomen.

Roaches in your shower drain can also die from long hot showers that flow into the drains. Bathing with strong antibacterial soaps and shampoos will also kill bugs like roaches, fruit flies, and springtails in the bathroom. After any long shower, the bathroom should also be kept dry from moisture that attracts roaches.