Carpenter Ants

[David White]

I had an Ant problem in an area where there was some condensation inside a wall. It was above the top plate on a standard stud wall, between beams that set on top of the plate. There is space between the beams that is boxed in with blocks to match the beams inside the house and a standard rim on the outside; cover by the sheeting. The space had vapor barrier but apparently was not air tight on the perimeter. WOW... those little suckers climbed 10 feet up to find a moist home. I found no trail. Spraying has eradicated them but before I close the space back up I want to be sure there is a "no vacancy" sign.

Any thoughts?

[hausdok]

Hi,

Yeah, ensure that you don't have any insulation in the attic touching the underside of the roof and blocking airflow into the attic. This will cause moisture-laden air moving up through the insulation to condense on the underside of the roof and then drip down onto that plate. You know the rest of the story.

Also, make darned sure that there isn't any Morning Glory, Wysteria or English Ivy climbing that wall or pushing shooters into it. When that happens, the stuff turns the wall cavity into a sweat box. Carpenter ants here seem to have an inate instinct to follow the stuff and will exploit the presence of moisture to begin mining.

Their climbing isn't unusual. This past summer I found a trail of them climbing up the chimney outside of a house and then entering the attic under the fascia. I went into the attic and found them moving down along the underside of the sheathing and then into a wall cavity below where they went all the way to the basement cripple wall before they nested. To an ant, there's no such thing as the straightest possible path is the shortest distance between two points.

ONE TEAM - ONE FIGHT!!!

Mike

[Neal Lewis]

I would use some glue boards to check for activity and wait until the Spring to close it back up.

I once had an infestation of Carp ants that avoided my treatment of the perimeter foundation by finding the telephone pole at the street and marching across the service drop to get to the nest in the house!

[Terence McCann]

In an older home I use to own they were nesting inside the bedroom doors (hollow wooden doors). There was a neat little square eaten away on the top and bottom of the doors located almost dead on in the middle. The little buggers would come out at night and make their way to the kitchen for water.

Neal has a good idea with the tack boards.

[carle3]

I had a house this summer that had a overhanging tree. The ants would go from the tree to the roof. The roof was a DIY (Destroy It Yourself) home owner job. He added a second layer of asphalt 3 tabbers over cedar shingles with no starter course or felt. The apex's would allow the cedar to get wet. An attraction these litte critters could not resist. They managed to destroy the fisrt course of roof boards. Owner to this day will not cut that tree down.