How to Use a ShopVac to Blow Borax or Boric Acid Into Crawlspaces to Kill Roaches

Cockroaches are flat-bodied, oval insects in the Blattidae family. Many species of cockroaches, commonly called roaches, palmetto bugs and water bugs, are common household pests. Not only are roaches a pain to deal with, they can damage your property and spread germs and diseases. With the correct operation of a ShopVac machine, you can blow a mixture of boric acid and sugar into your crawlspaces to kill the roaches.

Roaches can damage household items and contaminate your food.

Mix equal parts boric acid with sugar or flour. Stir the two together in a bowl.

Turn your ShopVac to the leaf-blowing setting. Not all ShopVacs can be used for this project because not all ShopVacs come equipped with the blowing feature. Make sure that you have or rent the correct ShopVac before trying to perform this procedure.

Put on a cleaning mask and protective eyewear.

Pour out a small amount of the boric acid mixture on the floor just inside the entrance of the crawlspace.

Turn on the ShopVac and blow the boric acid mixture into the crawlspace. The blow feature on a ShopVac is extremely strong, so you will only need to turn the machine on briefly so that the mixture is blown into the space.

Things You Will Need

  • Boric acid
  • Sugar or flour
  • Small bowel
  • ShopVac
  • Protective glasses
  • Protective mask


  • If you notice that the roaches are still roaming around in your crawlspace, you may need to repeat the process with more mixture. Another option is to open the crawlspace and place a lid of the mixture at the entrance. The roaches will be attracted to the starches, and the mixture will stick to their legs, eventually killing them.


  • Do not blow boric acid into any room of the home that is inhabited by people or animals. Do not place the mixture of boric acid and sugar or flour in any area that children or animals may come in contract with it.

About the Author

Jessica Jewell is a writer, photographer and communications consultant who began writing professionally in 2005. Her chapbook, "Slap Leather," is forthcoming from dancing girl press. Her recent work has appeared in "Nimrod," "Harpur Palate," "Copper Nickel," "Rhino," "wicked alice," "Poetry Midwest" and "Barn Owl Review." Jewell was recently nominated for a Pushcart Prize. She earned her Master of Fine Arts from Kent State University.

Photo Credits

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