Seconded on the baby powder. I have a slight gap where my side door (it's a French door that leads to the dining room and kitchen) and the threshold meet, which is where the ants were coming in. I sprinkled a fairly thick layer of baby powder across the threshold, and actually saw the ants who were about to come in turn around and leave! I haven't had a problem with them since, this year. I also sprayed white vinegar on the tile floors to erase the ant trails.
If any powder gets on the cats, you can just brush it off. I usually have to brush and Furminate my kitties more often this time of year due to the extreme heat (I live in the desert where it stays at 100-130℉ during the day from May to October), so it's not extra work for me.
If any powder gets on the cats, you can just brush it off. I usually have to brush and Furminate my kitties more often this time of year due to the extreme heat (I live in the desert where it stays at 100-130℉ during the day from May to October), so it's not extra work for me.