10 Tips and Strategies to Get Rid of Roof Rats

If you’ve ever had a mouse infestation in your house, you know how much these little rodents can ruin your life. But it can always get worse: you could get a rat infestation! Rats do all of the same things that mice do, they just make things even worse!

If you are hearing scratchings in the top of your closet, in the attic, or above you in the ceiling, chances are pretty good you’ve got a rat infestation already underway.

These greasy little rodents are some of the most common and troubling in the world, and sooner or later most people have to deal with them. And you better do it fast because they can do a ton of damage in a short time!

The good news is there are plenty of proven tips and strategies out there for getting rid of and preventing roof rat infestations. Keep reading, and I’ll give you 10 effective methods in this article…

What are Roof Rats Exactly?

Roof rats, scientific name Rattus rattus and better known as black rats for their typical color of dusky charcoal gray or glossy black.

Much larger than mice, and measuring up to 18” in overall length, they are sometimes known as ship rats and may be seen with dark or light brown fur.

Also, as the name suggests, roof rats like to go high and are excellent climbers, and that’s why they commonly are seen scampering around in trees, on rooftops, along power lines, and, regrettably, in residential attics and above ceiling crawl spaces.

They’re among the most common rats in the world, and the ones you are highly likely to encounter in and around human habitation if you live along coasts, rivers, or in the American South.

How Will You Know Roof Rats Are Around?

Common indicators for rodent activity will tip you off that these rats are around. Listen for loud scratching in walls particularly in the tops of closets, in the ceiling, or in the attic.

Keep an eye out for greasy trails left along baseboards, walls, rafters, and other avenues of movement that they use to get from place to place. Keep a close eye out for rat droppings also, which look like a shiny and dark brown or black pellet shaped like a huge grain of rice.

Roof rats are also bold explorers and won’t hesitate to gnaw through drywall and other materials to make holes that will give them access to food and water.

Make sure you check around any plants you have indoors because they will often raid trays and saucers to get a sip from runoff leftover from watering. If you spot droppings nearby or a greasy track near your plants, you’ve probably got roof rats.

Now, the best way to get rid of rats on your roof is holistically: you want to push back populations that are outdoors and too close to your home, prevent them from getting in the first place, and then eliminate with prejudice any that might have taken up residence. The following tips and strategies will help you do that…

Prevent Infestation by Eliminating Entry Points

Like with pretty much all rodents, one of the smartest things you can do when it comes to dealing with roof rats is to prevent them from getting in in the first place.

And because roof rats love to climb, they will tend to get into your home through access points that are above ground, usually around the roof, attic vents, soffits, and so forth.

This requires time and an eye for detail. Look for any openings, no matter how small, that might permit mice or rats to get in.

The rule of thumb is that a roof rat will easily be able to squeeze through any opening it is about the size of a nickel. Any place that their school can fit, the rest of their body can fit. It is true!

Block up these holes by any means necessary, and for irregular gaps take a wad of steel wool, stuff it in the hole, and then caulk it up to make a barrier that they’ll be reluctant to chew through. Be methodical and ruthless in your approach to closing up your home.

Cut Back all Tree Branches

The very next thing you should do after sealing all the gaps is to trim back all branches that can let them hop to the roof, gutters, or vents.

These rats, as mentioned, are superb climbers and it’s common to see them jumping through trees almost like squirrels. It’s an easy thing for them to run out along a branch and then right onto your roof or, if it doesn’t reach all the way, make a short leap for it.

Trim back these branches so they’re unable to complete the leap. 3 feet or so is usually adequate.

Make sure you pay particular attention to trees that don’t belong to you but are on a neighboring property line; the rats might be originating from there. Talk to your neighbor, if you need to, before cutting back a branch on such a tree.

Reduce Nesting Places Outside the Home

Roof rats don’t just live on your roof. They will nest in trees and shrubs, brush piles, and other places outdoors though they, as mentioned, prefer to get up off the ground if they can.

Once you’ve addressed the immediate perimeter of your home, expand your search for areas where they might be nesting. Check all large and thick shrubs, palm trees, wood piles, and similar to try and evict the rats that you find. Eliminate the nesting place entirely if you can.

Also, check sheds and other outbuildings where you have stacks of boxes and other containers carefully: these are picture-perfect nesting and breeding areas for roof rats.

Depending on your circumstances, you might not be able to completely get rid of all of these “rat hotels,” but you might be able to implement control methods around them or just make them less appealing to rodents in general.

Install Rat Guards on Utility Lines

Believe it or not, roof rats are a pretty common sight on power lines in suburban and some rural areas. I mentioned these rodents are excellent climbers, and you better believe they’ll scurry right up a power pole and then along the line, including directly to and sometimes into your home.

Wherever you live, it’s a really good idea to install rat guards on your utility lines, be they electrical, cable, or something else.

A rat guard is basically a giant dish that will clamp around the line itself and prevent rats from moving along it. Because they completely encircle the line, they can’t scurry under or over it, and very rarely will they ever attempt to jump over it and risk a fall.

They’re cheap and effective, but make sure you know what you are doing so you can install them safely. Call your utility provider otherwise for guidance.

Don’t forget to install it “downstream” from the nearest point where roof rats could jump from a branch or something else to the line, or else they’ll figure out a way around it.

Use Roof Rat-Repelling Fragrances

As strange as it sounds, there are some fragrances that can repel rats and other rodents. Rats, as a genus, have some of the most sensitive and delicate olfactory organs of any creature in the animal kingdom. This is a bit of trivia that we can use against them.

Things like mothballs, ammonia, concentrated peppermint, tea tree, or clove oil and specialty rodent repellent formulas can all make life intolerable for these little pests. If you treat areas where they are known to travel, nest, or congregate in and outside your home you might be able to drive them off or at least reduce their numbers.

You can soak cotton balls with your chosen solution and leave those around, apply oil directly to structural components, or sprinkle it on surfaces.

Try an Ultrasonic Deterrent

A high-tech solution to rodent infestation, ultrasonic deterrence can be a highly convenient and clean, but sometimes unreliable option.

These noisemakers work sort of like a dog whistle, emitting a loud, constant piercing tone that people and even dogs cannot hear, but most rats and mice can. It is with the same intention as using the repellent fragrances above: to make life in the vicinity of the device unbearable for the unwanted invaders.

The best part about an ultrasonic rat repellent is it you won’t have to mess around with restocking bait or deterrent, and you won’t be exposing people, pets, children, or other animals to any sort of poison, danger, or nasty smell.

The downsides are that for whatever reason they aren’t completely effective against all rats, and you will have to stay on top of battery changes meaning that can be annoying depending on where you have them placed.

Still, they tend to work quite well for local rat population reduction…

Place and Bait Live Catch Traps

When the rats are already in the walls, you’ve got to catch them and get them out. When that time comes, don’t underestimate the effectiveness and utility of live catch traps!

I know most folks tend to want to kill them, but you can make your life easier and get a better outcome by catching them alive and then disposing of them later or by turning them loose somewhere far away.

The best thing about live catch traps is that they tend to be self-resetting, and they can hold multiple rats at once. This means less work and less checking is needed on your part.

There are lots of good live catch rat traps out on the market, and you can always make your own easily from a large 5-gallon bucket and a few basic materials. Use bait like peanut butter, seeds, dried fruit, and jerky.

Once you’ve caught several rats, get rid of them and then put the trap back to keep working. By placing several traps in or near high-traffic areas, you can quickly get all of the rats out of your home.

Place and Bait Lethal Traps

Sometimes you just don’t have enough room to place a non-lethal trap. Alternately, you just don’t want to mess around with getting rid of the rats yourself one way or the other.

In such circumstances, lethal traps still make the most sense. You can use conventional “snap” rat traps, electronic shocker traps, and any other type that you prefer that will work in the setting where you need to place them.

As always, check your traps regularly to see if they’ve been tripped with or without a kill; if you have a bag with a rat inside, you need to get rid of it pronto before it starts to stink and then reset your trap for the next victim.

Get a Cat

Cats are an ancient and highly effective method of rodent control in all kinds of circumstances. Just having a cat around can help suppress rat populations because rats tend to be terrified of them. A good cat, left to roam your property and home, can decimate rodents large and small.

The only problem with using a cat for getting rid of roof rats is that these rats tend to be pretty sizable compared to mice (about 18” from snout to tail!) and that means you’ll need a correspondingly sizable cat. And the typical places that roof rats hide in, like your attic, are not ideal places to let a cat loose.

Nonetheless, a cat that still has sharp hunting instincts can ambush and kill rats that are coming out into the living space of your home easily.

Use Poison

As a last resort, you can use poison against roof rats. This method needs little explanation, and most of us already know that there are highly effective commercial and homemade poisons that will do the job.

The problem is that poisons don’t kill instantaneously. Rats will invariably eat the poison, get sick, start to suffer, and then retreat to some out-of-the-way place to die in.

That means they’re going to stink up your house something fierce most of the time. And if you thought a dead mouse behind the walls was bad, you haven’t smelled anything yet!

One or more dead rats decomposing in the nooks and crannies of your home will drive you completely mad or very literally drive you out of your home until it fumigates, a process usually taking two to three weeks. And even then, it might smell a little “haunted” ever after.

Then you’ve also got to consider the risk that poisons pose to other animals, including pets, and also children that might not know better. Poisons are effective but entirely indiscriminate killers, so always be extremely cautious when employing them!