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Insect spray in stud cavities?


We are renovating a 100 year old schoolhouse that we moved onto our property. We removed the plaster and lath and found a fair amount of box elder bugs and asian beetles. The former, especially cover the southern facade of the schoolhouse when the farmers pick corn and beans in the fall.

Should we apply some sort of insecticide to the stud cavities before we run electrical and insulate? We plan to seal (as best we can) any gaps in the siding and sheathing, but those little buggers are very determined. Thanks!


Re: Insect spray in stud cavities?

Get rid of all insects before you start your work. You don't need witnesses to see what you're doing. :D

Re: Insect spray in stud cavities?

I recommend that you use Boracare or Timbor. Both are primarily disodiumoctaboratetetrahydrate. Thats a Sodium Borate solution made up of 40% Boric Acid and 60% Borax. It is very safe for humans and on interior wood, it lasts for a very long time. It is not only a broad spectrum insecticide but it also stops wood rot and makes wood fire resistant. It is used in cellulose insulation for fire resistance. It is also one of the very few products allowed in historic preservation of buildings in environmentally sensitive areas.

The Boracare is more expensive, but easier to use. Just dilute with water and either brush on or spray on with a garden sprayer. Timbor is a powder and can be mixed in water or antifreeze before diluting. BTW, Boracare is the sodium borate mixed with ethylene glycol. But you have to heat up the water or antifreeze before mixing as the dry powder is hard to dissolve. Recommend that you do that outside on a camp stove.

Google these products for more information and sources. It has been used on several TOH projects.

Re: Insect spray in stud cavities?

Thanks Keith. We used Boracare on the floor framing while the schoolhouse was up on cribbing, so we'll give it a try inside.


Re: Insect spray in stud cavities?

the best thing you can do to get rid of Box Elder Bugs is to apply one of the leading brands of pyrethroid insecticide, such as Suspend SC or Talstar P. These are both proven to get rid of Box Elder Bugs and can quickly return your home to a pleasant bug-less state.

Re: Insect spray in stud cavities?

They sell special powder, it is what the experts use. Look under the name Sevan or sevan i think its called. YOu dont have to spray you can dust like the experts do...

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