we have the "sweet ants"...they search for food and more importantly they are drawn to moisture...since they are so small in size it is impossible for the house to be sealed off to prevent their entrance...they are also known to relocate thier lairs into the walls of the house

what i've done to stop them is to get 2 types of ant traps:

1. Terro ant traps...get both indoor and outdoor (active ingredient is Borax)...the out door traps are the best b/c they not only bait them but they keep them outside of the house...it also has a lot more poison in it (keep out of reach of cats/dogs)...it is the green thing in this picture


there is a 2nd type of trap is a small plastic trap where you cut at small hole where they can enter...put this where you know they may enter the house


2. a second trap i found is Grants...these are little bait traps on a stake you stick in the ground...put this around your house every 5-10 feet or known entrance points


by keeping them out of the house you are preventing infestations