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What Temperatures kill a Cockroach?

Cockroaches love to live inside a warm and humid environment. Insects, including cockroaches, are cold-blooded, meaning they can not maintain their body temperature within limits. Therefore, any significant changes within the environmental temperature are lethal for the roaches.

What temperatures kill a cockroach? A temperature above 115 and below 32 degrees Fahrenheit is lethal for cockroaches. Roaches can’t eat, mate, reproduce and mobilize at these extreme temperatures. For Roaches to survive, the ideal temperature is between 77 to 86 degrees Fahrenheit.

The high or low-temperature strategy comes in handy at eradicating roach infestation, particularly in restaurants and hotels. The same technique can be used at homes to eliminate roach infestation. I will be sharing complete information on using heat and cold to kill roaches.

Before you read further, just a quick question. Tired of cockroaches and looking for a permanent solution?

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4. Insecticide Spray to kill a reveled colony in a single shot

How Extreme Temperatures kill a Cockroach

A cockroach is designed by nature to live in warm and humid places. That is why roaches are in abundance in the last months of summer. Roaches love to live inside sewerage holes, basements, bathrooms, and kitchen cabinets.

Cockroaches are cold-blooded organisms, and their metabolism requires an optimum temperature to work appropriately. Moreover, roaches are designed with the open circulatory system, meaning that they do not respire through lungs but rather through respiratory openings on their bodies. They also don’t have red blood cells to carry oxygen.

The extreme heat or temperature above 115 degrees Fahrenheit ceases the metabolic processes, dries out vital organs, and dismantles the exoskeleton, resulting in the death of the roach.

On the other hand, at temperatures below 32 degrees Fahrenheit, the cockroach can not maintain the body temperature required for metabolism and respiration to work. As a result, the respiratory openings or spiracles freeze and cease to exchange gases resulting in the death of the cockroach.

It is important to note that cockroaches do not hibernate in winter as amphibians do.

Some of us are pretty scared of roaches, and some of us might have Katsaridaphobia, An Extreme Fear of Roaches!. Read this fascinating article to know more.

Ideal Temperature for Roaches

Cockroaches usually mate around the mid of summer. The roach’s egg starts to hatch around the end of summer when it’s warm and humid. For the first few days, the baby roaches can’t take care of themselves well, requiring an optimal temperature to survive. Please read Baby Palmetto Bugs: All You Need to Know to know more about baby roaches.

The ideal temperature for roaches to survive is 77 to 86 degrees Fahrenheit. Although the roaches can survive above or below, they are most active at this temperature.

Between 77 to 86 degrees Fahrenheit is the optimal temperature for the roach’s metabolism, respiration, mating, and reproduction.

Will Roaches Die in a Hot Car

If a car is parked in the sun on a hot day for one hour, the average temperature can reach 120 degrees Fahrenheit. However, if the vehicle stays for a couple of more hours under the sun, the temperature can reach well above 145 degrees Fahrenheit.

So we might question Will Roaches Die in a Hot Car? Yes, roaches will definitely die in a hot car if the temperature reaches above 120 degrees Fahrenheit for more than 45 minutes. Forty-five minutes time period is necessary for the roaches to die. The roach will recover if the temperature drops below 115 degrees Fahrenheit within 30 minutes.

One important thing to note is that there are certain areas inside the car where the air pockets maintain temperatures below 110 degrees Fahrenheit, e.g. the cool box, under the seats, under the cushions. So if a roach escapes and hides in these areas, then the roach will not die in a hot car.

Methods to kill Roaches with Heat

Heat above 115 degrees Fahrenheit is lethal for the roaches. Professional and DIY methods are in use for killing cockroaches via heat. The heat not only effectively kills roaches and nymphs as well as destroys the eggs. I will be discussing both of them in detail below.

Method 1: Dry Heat

Only professional exterminators use this method because of the danger of burns and damage to property. The area that needs extermination is sealed and covered with insulators. Then, any items that are heat sensitive are removed from the place.

Dry heat is blown at the targeted area for a few minutes and then allowed to cool. Any bug, including roaches, their nests, and eggs, is destroyed instantaneously.

It is advised not to attempt this method as a DIY project because of its risks.

Using heat to kill roaches can vary from state to state, the level of infestation, and the area being covered, but the average cost ranges between 1500 to 2000 USD.

Method 2: Wet Heat

Wet heat using steam is very effective at killing roaches and penetrating deep. It also avoids the risk of fire build-up. Both DIY and Professional help can be used to exterminate roaches.

For using steam at home, you need to buy a steam gun. To use,

  1. Remove any electronic equipment in the area that need treatment.
  2. Identify roach’s nest, eggs and nymph.
  3. Pre set the temprature to highest level using the knob.
  4. Aim at the area and blow out the steam for 3 to 5 minutes.
  5. Repeat the process if neccessary.

You can also mix water and a few drops of natural oils that repel roaches. It will not only increase efficiency but will also have a residual effect on keeping roaches away. Please read the Natural Palmetto Bug Repellents article to know which oil is best.

Methods to Kill Roaches with Cold

Roaches die below 32 degrees Fahrenheit because the metabolism ceases and the respiratory openings clog up. Therefore, the cold temperature method can also be used to kill cockroaches.

Confining cold at the targeted places is a difficult job. So, currently, the dry ice method is the only available technique to exterminate roaches.

Other methods are still in development and will be shared soon as available.