In such cases the weeps consist of small-diameter plastic, clay or metal pipes extending through the wall to a layer of porous backfill. Typically, weeps are arranged to direct water which may have entered an assembly from outside back to the outside.
A few of several safe household chemicals to use are vinegar, dishwashing soap and rubbing alcohol, according to an Oregon State University Extension Service publication called Using Home Remedies to Control Garden Pests, (EC 1586). The publication, complete with photos, is available free of charge online.
In the air, carpet, counter or cupboard, every home shares it's resources with these tiny, often unseen invaders. Pesticides are available for most common household insect pests, but these potent chemical compounds may be more harmful to you and the environment than the pests. Here are some natural, non-toxic ways to control household insect pests. Keep a small spray bottle handy, and spray the ants with a bit of soapy water.