This is the trick to permanent rat management. You absolutely must discover how the rats are getting in the building. If you do not discover this, and seal these regions closed permanently, then your rat problem won't ever go away. It's vital that you fully inspect the construction, every inch of it, and find all of the rodent entry holes.
Knowledge of both rat behaviour and building architecture is crucial. Rats can squeeze into incredibly little areas. Even rats which appear very big can slide in like jelly to the tightest of openings and holes - it is amazing to watch. They can occupy very small nooks and crannies within a home, from walls to ceilings, crawl spaces and attics. They can enter houses so many ways - gable vents, eave openings, ridge caps, crawl space vents at floor level, pipe entrance holes, where electric wires go in, soffit vents, fascia boards, roof joints, AC chases, beneath loose siding, etc etc.. They can chew their way in as well, of course, and that is what happens a lot of the time.
So how can you find all these areas? You inspect the construction, very carefully. You need to check in every little nook and cranny. From time to time, understanding of rat signals helps - they leave brown grease marks at entrance points, if used frequently enough. However, this isn't always observable. The entrance holes are often where you do not anticipate them, and you frequently have to crawl into tight spots and dig. Rats may also jump into areas you may not expect.
You also need to do an attic inspection. Start looking for indications of rats within the attic, such as chewed cables, droppings, paths in the insulation, rat nests, burrows, tunnels, brown grease, chewed wood, chewed insulation on pipes, etc.. This might help give a clue about how many rats you have, and where they're travelling, and if you stick to the paths, you can learn where they're coming in, sometimes.
How can you mend the holes and fix the house so that no longer rodents can get in? I essentially "rat-proof" the whole home, by sealing up all these entry holes. This is the ideal sort of rat avoidance available. They have really hard and sharp teeth, and may even chew through concrete if they need to! I use steel net, which I typically bolt . I also seal up the gap with a special polyurethane sealant.
And what if you've got rats inside your home, like in your living room or kitchen? If that's the case, they’ve discovered a means in the inner architecture, like a wall or attic, in the house itself. This is normally where there's a hole in the drywall, like where pipes or electricity lines move through the wall. Only after all the holes are sealed can you begin the rat elimination procedure. It is pointless to do so beforehand.
How are rats getting into the attic - They commonly enter via holes in the roof. But, they can also get in the attic from pretty much everywhere. If they get in the home from underneath, or by a ground-level opening, then they can simply scamper up the walls and into the attic. So the solution is: close any opening to the home. How are rats getting into the ceiling- They enter anywhere on the exterior of the home, then crawl through the structure and to the ceiling. How are rats getting into the crawl space - Normally through ground-level vents, or if you have nothing whatsoever obstructing your crawl space, as is the case in several buildings, then they simply waltz right on in!
How are rats getting into the garage - They most commonly get from the garage through the lower corners of the garage door, which usually aren't sealed very tightly. How are rats getting into the home - Rats get in the home via openings and holes outside. How are rats getting into the house - They get in the living area of the House via openings and holes in the drywall. How are rats getting into the kitchen - They get in the kitchen, usually where ducts and wires go through the wall, like a port, or the stove energy supply. How are rats getting into the restaurant - Rats get into bars exactly the exact same way they get into some other construction - through open holes on the exterior of the building. How are rats getting into the shed - Many sheds are not terribly well sealed, and obviously so of they could get in the shed easily. How are rats getting into the walls - They get into partitions quite easily, since they may squirm though any tight spot in a construction. How are rats getting into the flat or attic - Same as any other construction. How are rats getting into the oven - Stoves and ovens have openings in the bottom and I've eliminated dead rats from ovens several times through the years. How are rats getting into the bathroom - The come up through the sewer pipes, obviously. Without water, it is a cinch. With water, it is very unlikely. So long as there isn't water from the pipe, it is the ideal rat tunnel!