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Carpenter Ant Damage To Wall Stud

I just started replacing clapboard on my house only to find a major infestitation of carpenter ants after removing some of the sheathing where it had rotted away from the runoff from a drain spout. Yes that will be fixed.

One of the studs behind the sheathing was damaged by the ants, but the carpenter I had working on the house said the 2x4 stud was still good; that the major 3.5" of the stud width was still good.

With the extermination completed, he will be replacing the sheathing, installing Tyvek and new clapboard.

Given there was some damage to the stud and one of the garage roof joists for the attached garage, is there anything else that should be done with the damaged wood to avoid its further deteriation over time?? Or is buttoning it up as planned sufficient based on my carpenter's recommendation?


Re: Carpenter Ant Damage To Wall Stud

It depends on the extend of the damage, but don't think that your carpenter is saving you money or doing you a favor, by not replacing this stud.

If I were working on your house, I'd replace it.

A. Spruce
Re: Carpenter Ant Damage To Wall Stud

Depends on the situation, something that we cannot determine from a post on a forum.

I am inclined to agree with DJ about replacing the stud. Do you "have" to, probably not, however, you don't want any eggs or larvae left behind to hatch and reinfest the area. You've already got the wall opened up, it is cheaper and easier to just replace the stud, if for no other reason than peace of mind, than to close it all up and find a reinfestation occur.

Re: Carpenter Ant Damage To Wall Stud

We use the standard 'screwdriver test' - jamb a flat head screwdriver into the offensive stud. if it penetrates much further than a good stud, then replace it. If the screw driver doesn't make much more of a dent then leave it alone.

The eggs can be anywhere not just on that particular stud.

Re: Carpenter Ant Damage To Wall Stud

I don't know how far you are into this project, but there is something you can do and that is to treat the wood with a sodium borate solution. That will prevent re-infestation of the carpenter ants along with preventing infestation of other wood damaging insects like termites, even the Formosan Termite.

You can Google for products like Timbor or Boracare. Boracare is the most expensive, but the most foolproof and you should only need about a gallon for your entire house. Timbor is a powder that has to be mixed with either water or antifreeze. To be as effective as Boracare, you need to use antifreeze. To mix it, you will want to do this outdoors on a camp stove or gas grill and use a pot that you will never cook in again. You have to heat the antifreeze up to 280°F and it will give off toxic fumes. Stay upwind.

I don't know why you can't mix it with boiling water instead and then add the antifreeze later other than water will not absorb as much of the sodium borate as antifreeze will.

If you can't wait for the shipping, you can make your own sodium borate by hitting the Dollar Store and getting 2 one pound containers of roach killer that is 99% or higher Boric Acid. Then hit the grocery store for a box of 20 Mule Team Borax. Mix 3 pounds of Borax with the 2 ponds of Boric Acid powder and there you have it. Heat up a gallon of antifreeze (cheapest will do, even used is ok as long as you determine the concentration level of it first). Once it is mixed in with the antifreeze, you can dilute the antifreeze with up to 2 galloons of water. If you are using a premix or used antifreeze at 50%, don't dilute, at least not very much.

Put this mixture in a garden sprayer and use it to spray the wood. You can also paint it on the wood with a paint brush but that takes longer. Saturate the wood as much as you can. Be sure to do the sills and ledgers. You can even use it on the floor joists and ceiling joists, but those can wait until the current project is done.

BTW, Boracare has been used on a couple of TOH projects.

Re: Carpenter Ant Damage To Wall Stud

It is always best practice to replace studs that are damaged beyond that allowed in the code for your area.
In the earthquake prone areas of California, a damaged stud compromises the structural integrity of the building.

Re: Carpenter Ant Damage To Wall Stud

Be aware that carpenter ant colonies set up one "parent nest" with a few "satellite nests", in healthy trees, shrubs, logs, branches, wood piles, under rocks, crawlspaces...if you get a satellite nest and not the parent nest the colony just moves and you wind up with even more nests the next year.

Then some of the Queens get out, and set up a second colony, a second parent nest, and second satellite nests....etc. If you think you might have multiple colonies, put one ant from each in a cup or jar together...if they try to kill each other-they're from different groups, and you need to find two or more parent nests...

(I unwittingly bought a well established, multiple colony house, and have learned far more about carpenter ant behavior than I ever wanted to know!)

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