Although people don’t like rats, rats love people. They love the places where people live. They love the foods that people eat. If they come upon a human-inhabited place that offers them food, water and shelter, they will stay. If the hospitality's shut down, they are likely to move on. That principle of rat behavior underlies methods for keeping rats away from your home.
1. Block rats’ paths of entry into your home and outbuildings. Rats can squeeze through cracks 1/4 inch wide and through holes the size of a dime. Patch cracks and holes in foundations with premixed patching compound on a trowel. For large cracks and holes, patch with hardware cloth and secure the metal mesh by covering it with patching compound. Nail up any loose boards or siding on wood frame walls. Replace missing boards or siding. Repair or replace rotted wood.
2. Replace plastic window screens with metal screens on all windows. Install springs or closers on exterior doors. Caulk around pipes and wires where they enter the home. Cut out hardware cloth collars with tin snips to fit snugly around pipes and wires. Secure the collars to the wall with nails or construction adhesive.
3. Deny rats a food source. Put trash in metal or hard plastic containers with tight-fitting lids. Feed pets during daytime hours and remove uneaten food. Pick fruits and vegetables when they ripen. Remove fallen fruit from the ground and compost or discard. Store foodstuffs in rat-resistant metal or plastic containers. Clean up food spills promptly. Fix plumbing leaks to deny rats a source of water. Don’t store food in your basement unless it is in rat-proof metal containers.
4. Deprive rats of a place to shelter by keeping your yard and house neat and clean. Keep your lawn mowed and lawn edges trimmed. Remove brush and junk piles, old tires and appliances, and any other trash. Clean out trash and yard debris from underneath porches, decks and stairs. Store usable equipment and other items on racks or platforms set 18 inches off the floor and 1 foot away from the walls in basements and outbuildings. Trim trees, vines and bushes to maintain a 4-foot gap between the vegetation and your roof and walls. Indoors, clean behind and beneath appliances and cabinets and keep them tight against the walls. Keep trash out of closets and cabinets. Don’t allow dirty dishes to pile up.
Things You Will Need*.
Metal or hard plastic trash containers*.
Metal or hard plastic food containers*.
Hardware cloth*.
Caulking*.
Premixed concrete patching compound*.
Trowel*.
Tin snips*.
Construction adhesive*.
Hammer*.
Nails
more @ http://homeguides.sfgate.com/prevent-rats-coming-inside-house-31613.html
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Really nice write-up