The best way to control mice and rats is to make it impossible for them to enter your home.

That can be difficult with mice because they can pass through an opening only 3/8 inch thick. In general, all openings greater than 1/4 inch thick should be sealed for rats.

Check all openings around utility lines that enter your home, around service conduits such as water pipes, electric wires, air- conditioning units, drain pipes, and vents should all be sealed. Also, check for broken windows and un-screened vents. Vents should be covered with metal grill-work backed by rust-resistant screening. Roofs should be checks to see that shingles are down tight and sheathing is complete. Check roof ventilators, screen vents, and in-wall vents. Copper mesh stuffing should be placed in weep holes around brick foundations.

Make sure you check under sinks where pipes enter the wall. This is a great area for mice and rats to enter your home or business. Copper mesh stuffing, coarse steel wool, sheet metal, hardware cloth, and mortar can be used to seal the spaces around these areas. Just use your imagination.

These are probably not all the areas that mice and rats can enter your home but do cover almost all of them. Like I said above, just use your imagination and remember to cover all the small holes and cracks.