Rats in your house? Here's the ultimate guide to achieving a humane, immediate, and permanent result. I developed this method during years of running my eco-friendly wildlife control business. We actually advertise same-day rat removal, and we consistently deliver!
Most of my customers have tried some sort of DIY solution before they commit to a professional. Everything from over-the-counter poison, sonic emitters, mint oil, radios, lights, wolf pee, ammonia-soaked rags... it's all a bunch of BS. You have rats in your structure, you have a structural problem!
Follow my process to identify and mitigate the root cause, improve your structure, and permanently remove your rats.
Find and address the active and potential rat access-points
This is where the problem starts and ends. If you have rats in your structure, it means you have gaping holes allowing free access. Period. Even if you nuke every rat in your structure, more will come. Once an access is established, rats will inevitably create scent/pheromone trails that are easy for other transient rats to pick up and follow. For this reason, structural rat problems are literally never-ending until you effectively pest-proof the access-points, thereby cutting off the 'flow' and isolating your populations. Pest control companies love to ignore these accesses and sell people recurring poison services; this is essentially an attempt to continuously profit from an endless problem, at the customer and environment's expense.
The key to rodent-proofing a structure is to literally check every square inch. Don't stop once you find one active access-point; they often have more than one, and if they don't, they'll be probing for weak spots to create new ones. It is imperative you take your time and do this properly - if you miss one hole, you might as well have done nothing at all.
When you find the main one(s) - and you'll know - don't exclude them just yet. This is where you'll install the one-way doors - I highly recommend you pick one or two up.
This is the most common area for rat access-points, especially for roof rats! Roofers care about one thing: water. We get calls to brand new, multi-million dollar structures that have rats move in right after the new owners do. Structures old and new are built with inherent flaws that allow easy access - I consider this a serious building code failure.
If you hear scratching or squeaking coming from the roof or attic, your first task is to head on up there and check out every square inch. If your roof is high, steep, or you are uncomfortable with heights, then please hire a professional. Just make sure they specialize in pest-proofing and one-way doors - always read reviews. Also, please don't do this when it is raining...
Below are the common access-points on a roof:
Gutter lines have a few issues: the fascia (the board the gutter line is attached to) degrades quickly due to the frequent exposure to moisture, there can be a built-in gap between the fascia and the roof decking, and there can be small gaps/seams at the inner and outer corners. Rats will rarely pick a point of a flat board and start chewing, instead, they like to identify small gaps and flaws and exploit them.
Checking your gutter line is as simple as tossing a ladder up every few feet along the line and have a good look, paying special attention to corners. Make sure you lift up the shingles to see how the roof decking meets the fascia; if there is any gap then you need to be checking the entire line. If you check multiple spots along the line and everything is tight, then you can likely space out your inspection points and just focus on corners. If there is an access-point, you'll know it by the chewing, droppings in the gutter nearby, and likely black grease marks from the rats' fur.
To exclude a gutter line, simply cut long strips of steel mesh (usually 3-4" wide x 4' long) and screw them into the gutter line to cover the gaps. You might have to do a small section, or you might have to do the entire line. If there is any gap at all, I would recommend addressing it all.
Soffit angles are an extremely common rat access-point. This is where the soffit line of one roof section meets the shingles of another. It might look tight where the soffit line ends, but there is little holding the soffit in place. Everything from rats to raccoons go house-to-house testing soffit angles; raccoons will get in the angle and use their head to try to knock the soffit out of place - we hardly see a house with roof access in the Lower Mainland without dents in their angles! If it is an active access you'll notice it easily, if it looks tight and clean then just give it a good push to test how strong it is. Not every soffit angle needs to be excluded, but if it is flimsy then you should address it.
These can be tricky to pest-proof. The key is to cut steel mesh the same width as the soffit line and about 4' long. Tack it onto the line, run tight into the angle, and then screw it down onto the shingles. Pick up some roof sealant to cover your screws to be safe, but usually, you'll be under the cover of the soffit line above so leaks aren't much of a concern. Take a good look at your finished product, if there's more than a 1/2" gap then you either need a bigger piece or just install some filler pieces. This doesn't have to be pretty - you'll hardly see it from the ground - but if you can pull it out of place then it likely won't last. Don't underestimate these things!
This is usually where people think the rats are accessing the roof, but it's not as common as you would think. If there is no grating on the chimney hole then you have a few options. We usually cut a piece of mesh just slightly bigger than the opening and press it inside; the mesh will bite and hold with enough strength to be effective. You can also glob some of your roof sealant around the chimney opening and stick screen over top of the hole. Another option is to buy legitimate chimney caps, but I would say they are hardly worth the price/effort.
Plastic roof vents
These shouldn't exist! Often overlooked, plastic vents are an easy access-point for a variety of larger pests. Although they look sturdy from the outside, anything that squeezes underneath the overhang has only a plastic bug mesh to chew through - they literally go through it like butter. The best thing to do is to grab a flat nail-puller and gently pull the vents completely off the roof to expose the hole. If you don't have an attic hatch, this is a great way to get a look inside!
Careful here, depending on the state of the shingles how many nails/amount of sealant the roofers used, it might be better to leave the vent on and exclude from the outside. This is achieved by simply screwing a strip of mesh directly into the vent, just so it blocks the 1" opening at the bottom.
Pretty simple; if you can see branches laying on your roof, you should cut them back. Use the 4-foot rule.
If you're seeing/hearing activity at ground level or in your basement, you can make the assumption there are access-points at ground level. You should be checking either way. Again, inspect every square inch!
Take an initial walk around and check your walls from the ground up - there likely isn't a random hole in the middle of the wall, but look anyway. Take note of any plastic vents or metal vents that might have screens missing or loose.
This is likely it. First, move EVERYTHING away from the wall/foundation. If you can't see it, you don't know if there's a hole there. Additionally, if you confirm there is no hole but you replace the debris, you are just creating a safe, covered void from which rats can safely chew on your structure for hours on end, eventually creating an access-point.
If there is a hole in the foundation, it is likely where the foundation meets the actual wood structure of the house. There might be an obvious hole, or it could be hidden underneath the siding - it depends on your specific house. If you can get your whole hand underneath your siding then you need to determine whether or not the siding is hiding weak infrastructure or not. The easiest way is to put on a glove and start feeling around; if you can feel solid wood at the top then you're likely fine, if you can't find the top the void then I would suggest excluding it. Fortunately, this is pretty simple. Cut some 3" strips of mesh and give them a bend down the middle (the long way), then push it up into the void and let it expand, that's it!
Seems obvious, but it is often overlooked. Give all your doors and frames a good look - if there is a noticeable gap you can either cover it with mesh or flashing, or there are rodent-proof door sweeps which can be purchased and easily installed. These could be hard to get depending on your area; the company is based in the US and doesn't have a huge presence yet.
These can be tricky! Builders often allow for flaws such as short-cut boards and unfinished surfaces behind front/back steps. They know the step is permanent, and no one will see it regardless. The problem is that rats love denning under steps, and if there is a void with an exposed flaw, you can bet they'll try to exploit it.
You can usually tell if this is the problem from simply inspecting the perimeter of the step. Look for trails, digs, droppings and nuts etc. If you think rats might be under the step and there is activity that corresponds on the interior, then you should assume there is an access-point behind it.
Large wooden steps often allow access underneath with a little work - this is the best-case scenario. Get under there and inspect the exterior wall, you'll see an obvious access-point if it is there.
If there is no access - such as a concrete step - then you'll have to do some trenching. Dig a 1x1' hole around the perimeter of the step, and affix mesh from the step (just above the ground line) down into the trench, and then out, effectively creating an "L" shape. This can be tough if there are roots, but if it is necessary then you'll just have to get through them. If you're doing this with a concrete step, ideally you can get a hold of a concrete drill to affix the mesh. These can be rented for cheap, or I bet one of your neighbours has one. Punch a hole every foot and use concrete screws with washers to keep the screen tight to the step. This looks tidy and is as permanent as it gets.
Same deal as steps, but probably a little more common. If you think your deck is hiding an access-point, you have a couple of options. If it's high, crawl in there! If it's low to the ground, you can pull up the boards close to the house and work that way - this often works!
if the boards are running perpendicular to the wall or you don't want to risk damaging your deck, then you'll have to resort to "L" trenching as mentioned above. This might seem like a big job, but it usually goes fast. It's also something that your neighbourhood teenager is perfectly capable of doing for a few bucks.
Install one-way doors
One-way doors are hands-down the most effective tool for removing rats from your home. Rats dehydrate in as little as 12 hours, so they must venture out nightly to find food and water resources. By pest-proofing your the minor/potential accesses and installing one-way doors, you're essentially turning your structure into a one-way system. They can leave but not return, and this is how you get the immediate result. It doesn't matter if there are 5 rats or 20, they ALL leave through the door.
It's best to install mesh around the access-points and leave a 2x2" hole to install the door over. There is no special way of doing this, just make sure it's on there nice and tight. Ensure that the door is the right way up - rats should have to push under the door to leave.
Set your traps
The one-way door and pest-proofing are what really gets this job done, so traps aren't actually necessary. However, if you're comfortable with it, I would recommend setting traps in active locations on the interior, as well as in secure stations on the exterior. Although rats will eventually leave through the door, they don't like it. Rats tend to back off from the door and explore other options first - if they have already breached the living space then they might push inwards, or they might decide to try and chew something they shouldn't, like a pipe or wire. Stations on the exterior will catch any that are probing the structure over the coming nights for re-entry. Again, you're likely fine without these, but this is a good opportunity to do some humane population control, as well as ensure they don't return.
When all of this is done properly, every rat will either get caught or vacate through the door in 24 hours. You've left them no other choice! For those of you thinking that you've already had no success with snap traps, it's because the rats had no pressure to engage with them. By cutting off access to their resources, you have now put them in a state of desperation; you hardly need to bait traps in this situation.
I have my own special recipes, and those aren't free! However, you'll certainly be successful with these household go-to's:
- peanut butter
- nuts (stuck to something sticky)
Remember, less is more! Put a small amount of bait on the trigger, and make the rat commit to the pan to get the treat.
Run program for 1-2 weeks
You'll get your result in the first night or two, and maybe catch some stragglers on the exterior in the coming days, but run the program until things are quiet for at least a week. Better safe than sorry!
Once you're sure the rats are gone for good, go ahead and remove your doors and interior traps, and close up the holes. Many people will continue to run the exterior stations - it can't hurt, but if you're not seeing any activity then you're probably fine to store them away until you notice them again.
This might seem like a lot of work, but very few structures require all of the described work. Usually, you're dealing with one or two main accesses and maybe some weak spots you're unsure about, so you fix. We finish most of our pest-proofings in 1-3 hours, and the follow-up work takes minutes.
Lastly, forget rat poison!
This should be first, but if you're actually going to follow this guide, then you'll have read this far.
Regardless of how bad your problem is, poison is NOT the answer. Aside from the myriad of inhumane and environmentally degrading factors, the best result poison will get you is some stinking carcasses in voids you can't access without serious a serious house-surgery. I'll just lay out some rat poison facts for you:
- you can never tell how many rats hit the bait, whether or not they died, nor where they went after they did/didn't die
- rats will have to commit to the poison anywhere from 2-8 times over a couple of days to get a lethal dose if they die at all - traps take ONE commitment
- rats that don't die can become resistant, and even become more likely to pass on diseases due to their compromised immune system
- rats do not die peacefully, and they do not seek water and die outside. Most often they will die in your wall or floor and create a stinking health hazard
- rodenticides are responsible for countless secondary poisonings, from basic scavengers to birds of prey, and even larger predators like foxes, coyotes, and cougars
- 10,000 children per year in the US are hospitalized due to contact with rodenticides
- the list goes on... buck up and set a snap trap
Sometimes these things can be tricky, many people will do better off with hiring a professional from the start. If you're in the Lower Mainland, BC, give us a call! If not, arm yourself with this knowledge and call around for a company that doesn't just push a poison service. If you need advice, just reach out here. We're really here to help!
- basic hand tools - drill, snips, pry bar, etc.
- screws, washers, staple gun
- roof sealant
- 1/2" steel mesh
- one-way door - you can find these cheaper through local pest supply stores, if available
- Classic Snap Traps and/or Trex Traps - either will work, but I recommend classics. Don't go for the electric ones, nor poison.
- Xcluder stuffing - optional, but handy! Again, you can likely find cheaper
- Xcluder door sweep - your best bet if you have doors of concern, however, screen or flashing can work
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