Hello Jane! Today I was here for your one time service! I performed a visual inspection of the sliding door where you notice the carpenter ants. I applied an ant gel bait to the cracks and crevices of the doorway. I applied a liquid treatment to the doorway. I placed carpenter ant granular in the corner near the door and I sprayed the exterior to help with prevention against ants and other general pests. Please allow 2-3 weeks for best results of the products! Thank you for choosing Green Pest Solutions!