Look for activity near appliances, air conditioning and heating ducts, utility lines, plumbing fixtures, drains, and pipes. Observe worker movement and look for the focus or source of infestation. Make diagrams of worker activity if necessary. Use traps baited with sugar, syrup, or grease to confirm observations. Maintain records of all inspection discoveries.
Structure infesting ants usually indicate a moisture problem in the building.
Check where pipes enter or exit walls. Inspect for galleries excavated in wood by sounding with a blunt instrument or probing with a pointed object like a screw driver. Check joints in wood or additions to buildings, hollow wooden columns, sills downspouts or grading where water collects or drains toward the structure. Check for leaking roof valleys, improper flashing, and around chimneys, vents, and skylights. Look at water sites.