Mice/Rodent Problem in Home -- Stuck in Walls

11 Replies

I own a duplex in Philadelphia and my tenant downstairs calls to tell me that they have a mice problem--they can hear them in the walls and catch them in the kitchen and basement. I have been inside of their unit several times and they are not the cleanest tenants--often finding food, crumbs, dirty dishes, trash etc just laying around the house. I put down some traps in the home (kitchen and basement) to help get rid of them.

I've live on the 2nd floor and I have never had a rodent, bug, or insect problem--until recently. I've noticed a rodent problem but they appear to be stuck in between the walls of my home. My contractor says that they must have ran up through the pipes from downstairs. They cannot access my unit because all of the holes and corners are sealed up and I keep the home clean but the noise drives me insane because they are scratching away in my bedroom closet and I am paranoid that they will scratch their way inside.

Is there anything I can do to get rid of them scratching away between the walls of my home? is there an affordable fix or resolution without having to spend hundreds?

I'm certainly not a pest control expert, but I'm pretty sure the only thing you can do is set traps. I've talked to pest control companies and that's all they do, and charge a bunch of money to do it.

Since they can't get into your house, you will have to set the traps downstairs, which you have already done. I don't think there really is anything else you can do.

This won't be a permanent solution (especially if your tenants are leaving food around) butmice do hate the smell of peppermint. I had mice moving in one fall and I put cottonballs with peppermint oil in the places I was hearing them. They went elsewhere! This might not solve the entire problem -- but it might keep them away from your closet

They're not "stuck" in the walls, they live there. Also, if you're hearing them in your walls, they're not staying there at night. Just sayin'. 

Mice can squeeze through a dime sized hole or smaller. Try and seal up any exterior entry points as best you can. Also, if you're in a row home and your next door neighbor has mice or bugs, you most likely will too. Not much you can do to keep them from spreading between units unless you were to demo your walls and seal the party walls against rodents. You can clear your unit of mice but they'll be back in a few weeks or months in a row home.

Lastly, if you put poison out, you'll kill them...slowly. They go to die in your walls and they stink to high heaven for a few days till they dry out. Sorry to be the bearer of bad news but there's certainly no easy solution. 

@Jean Bolger  

Thanks! I will definitely have to try that peppermint trick.

If you live in an urban setting I would confirm if it is really mice. It could unfortunately be rats if it is just on the lower levels. Here in Chicago people often think they have mice and its not unusual for it to really be an rat issue. With any rodent issue its all about exclusion otherwise its a never-ending battle you likely will not win.

If it is a rat issue don't ever use poison inside. If he kicks the bucket you probably won't ever find it and they smell way to long.

 If it was me I would approach it from the outside on in. I would recommend exterior bait stains over anything else starting out. I highly recommend domyownpestcontrol.com they have great pricing and are very reliable. First strike soft packs and final blox are the way to go as far as rodenticide (d-con will only be eaten by probably less than half and they can be resistant to the poison). Many rodents will actually have different palates and is a great idea to offer a good mix for best success. They have many options for exterior bait stations but they are the key to overall success.

Next you need to get things sealed asap are you will get nowhere fast and go crazy dealing with them. Make sure doors have door sweeps, bushes and trees trimmed away from touching structure, ac lines and pipes going into property are sealed (silicone or steel wool), and general holes into property need to be sealed (hydraulic cement is great for patching stone/cement and steel wool for everything else).

Then to tackle the interior issues. Obviously snap traps (extended triggers baited with reeses, pnut butter, bacon, or vanilla extract) are the way to go to remove as many as possible as quickly as possible. I would use traps and bait for best results. You can normally have success with small "aegis" bait stations for the interior but there is always a small risk of smells. The bait stations need to be put in areas of activity (under sinks, behind stoves, crawl spaces, attics, and behind refrigerators).

I have cleaned out properties many times with these methods. The key is exclusion and keeping populations low with bait stations so you never have the issues again.

I live in a Philly row and had a similar problem. Mice were in the ceiling and wall cavities, but not in my living spaces (I have a cat and keep the place clean). My neighbors on both sides are not clean and have mice in their walls AND living spaces.

First thing I did was seal all the entry points on the outside of my home. That didn't solve anything since they were getting in through my neighbors.

Next thing I did was cut a small hole in the ceiling where I heard them, and a small hole in a wall where I heard them. I dropped a bunch of mice poison in there and sealed the holes back up.

After a few days I heard much less mouse movement. After a week there was none!

Be careful though. If you poison the mice and then a pet eats them, the pet will die.

The only solution to your problem is by calling City Best Pest Control. They offer high-quality pest control services at affordable rates. You will be happy to know that they provide pest control services in your city Philadelphia. They will surely help you in overall rodent pest control.

Hi--this is a re-posting I just wrote on another forum. 

We've been having this problem in one of our rentals/a rowhouse (connected to other houses) and have called 2 different exterminator co. --1st co. came 1 yr ago and in the spring we called a different co. as maybe the 1st co. didn't seal all the holes or what. The 2nd co. said they could not find anymore holes that the 1st co. didn't see. We've set baits, traps, etc. and were still having problems as all the holes that could be sealed were done but still the problem continued. Long story short, our tenant found suggestion to put out peppermint oil on cotton balls all over the house. Make the smell strong and so far so good! No mice noise between the walls, none coming in!

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Poisons do work and rarely cause any smell. The carcases quickly dehydrate however the trick with using poison is to insure there is no open water source inside the home. Once mice are poisoned they need to drink. If there is no water inside they will leave the building for water and will die outside the home.

Snap traps are really only a band aid approach. If you do not use poison inside and out you will not solve the problem or prevent them from returning.

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