It may not be that difficult to locate the rat nest if they keep you awake all night by shuffling around in the attic. But many rats stay close to the ground and live near the walls of your home's foundation. In order to find the rat nests in these situations, you may need to get under your house in its crawl space. Once down there, you should be able to find the burrows and figure out how large your rat family is. Make sure to wear a protective mask and gloves when working near rats. Rodent urine is supposed to show up under blacklight if you have one of those handy. There is an LED blacklight in flashlight form if you want to dish out about 70 bucks.Once you have located the rat colony, it's time to find out how they are getting into your home. Rats can squeeze through an opening ½ inch wide. Look around the outside of your home for potential entry points. Pay close attention in order to detect cracks in the foundation and excess gaps where wire or pipes enter your house. Some rats will be able to burrow under the foundation, so look for holes in the ground around your house. Work your way up from the ground to the roof. Rats are expert climbers, so they could be getting in under the eaves of your roof.Now that you have located the entry points, it is time to close them off. You will want to seal up those holes with something the rats won't be able to chew through. Heavy gauge metal meshing, sheet metal, cement, or mortar are the best rat-proof barriers. Fill in the cracks in your foundation with cement. Some people put sharp things in the wet cement to deter the rats from digging it out before it dries; broken glass seems to be effective for this. Cover the other holes with the metal sheeting and fasten it tightly with external screws. You can use expanding foam or caulking to seal a hole, but without something metal to block them, they will just chew their way through.The best way to catch a rat is with a snap trap. They look just like mouse traps except bigger. They are cheap easy to set and easy to empty. There are other types of traps available, like glue boards, or the Rat Zapper. Glue boards are extremely ineffective and not lethal; they're just torturous. The rat zapper lures them into a box and delivers a lethal shock. Many people believe the shock is not strong enough for the big rats, so that leaves us with snap traps. Set them with butter or peanut butter for bait. Check them daily or hourly depending on how many “snaps” you hear. When disposing of rat bodies, wear gloves, double bag the bodies, and place them in an external garbage bin.Once the sound of rat traps snapping shut has died down in your house, it is time to clean up the mess the rats left behind. To clean up rat feces, nests, and what not, you will want to wear goggles, a dust mask, and gloves. Once you have donned your apparel, survey the damage and determine what needs to be replaced. Frequently insulation will be soaked with urine; bag it up and throw it away. You can use a blacklight to check and see what has urine on it. To clean up feces and other small particulate matter, use a shop vacuum. For things that can't be removed, like wood and other parts of the house, use an weak solution of bleach (1 Tbsp bleach to 1 gallon water) or use an enzymatic cleaner.Rat Control
After cleaning up the rat mess, it will be a good idea to continue setting rat traps and checking them on a daily basis. Don't put too much bait on the trap, as that will just encourage more rats to come around. It may seem frustrating to have to check the trap everyday, but if you catch a rat, it gives you the opportunity to get a head start on shoring up your house again for the coming months. Because, even after going through all the work of sealing up your house and trapping the remaining rats inside, they might come back and find a new way in. Keeping rats out of your house will be easier if you remove things that attract them. Keep food containers covered and sealed inside and out. Move trash cans away from the house. Keep the ground free of debris, like piles of leaves and brush. Make it harder for the burrowing rats to dig in the ground around your house by adding rocks. And, if nothing else seems to work and you are at your wits' end, just call a professional. It's alright. You gave them a good fight. At least the exterminator will be impressed with your knowledge of rats.