PEX vs The Rat

Larry Weingarten

Hello, I started using PEX in 1991 and have always heard the rumor that rodents can chew through it. I've never actually seen a photo or known anybody with first hand experience of this. To me, it had attained urban legend status. So, imagine my surprise at seeing this! It's like staring into the eyes of a unicorn No doubt others here have run across this many times, but for those who wondered about the myth, here's proof.

Yours, Larry

EBEBRATT-Ed

@Larry Weingarten

You really need to keep those rats well fed so they stay off the pex diet LOL

DZoro

Had red squirrels chew into the bottom of my camper. Then chewed pex lines that crossed through the main frame. That was a pita to repair.

JUGHNE

You need to use larger PEX.
We use Gopher Pipe for UG electric services here.
It is SCH 20 2"PVC, in 20' lengths, you still have to install direct burial wire inside and use SCH 40/80 for risers.

The idea of the size is that gophers can not open their mouth that large to chew.

plumbob44

I've been planning for over 30 years and using PEX for at least 20 years. I have seen this only once.

NoeVillegas

Here in Chicago they do not allow the use of PEX but I’ve come across mice chewing through the plastic ice maker water supply lines plenty of times.

Alan (California Radiant) Forbes

I've only had one job where rats ate through PEX in the attic. The PEX was for a future zone and did not have water in it.

More recently, rats ate through this control wire in the attic for a residential steam system. Not for steam heating, but for steam in a shower.

flat_twin

Rodents chewing on vinyl wiring insulation is a constant battle for telco techs. We were told vegetable oil was used in manufacturing the vinyl and that's what attracts mice, rats etc.

On the other hand, squirrels will chew through aerial aluminum enclosures when they're seeking salt. The only thing that worked for that was to hang a salt lick near the damaged enclosures

BumpyHed

OLD SCHOOL KNOWS BEST. THANK GOD FOR CHICAGO. NO PEX.

Larry Weingarten

Hi, This was a pretty extreme case, rats were taking over inside of the house as well But, the lesson was driven (chewed) home for me that if I'm installing PEX where there is evidence of rodents, I'm going to run it in a conduit or sleeve. I suspect the smaller the PEX, the greater need for conduit, just as @JUGHNE says!

Yours, Larry

WillieJ

House wiring too. I found this while rewiring some ceiling light fixtures in my house.

Intplm.

There is a unit that you can use that I purchased at home depot in the rodent / poison section years ago. I now use it at every building that I own or have owned. This item works! Plain and simple just works. It is called the Victor Pestchaser.
I bought it out of desperation. Mice and other critters getting in no matter what I did to stop them. I Just didn't think it would work. I was a typical naysayer.
It is not a poisonous bait, but a noise maker that only rodents can hear. It is about the size a cadbury chocolate egg. It plugs into a outlet and has a small night light on it too. I now swear by them.
Before using this, I was poison baiting, trapping, using professional exterminators, you name it, I tried it. And what stinks about the baiting and trapping that I was trying had the little critters getting into the house before the poisoning or traps could take affect, and who wants these vermin in the house to begin with ? Not me !
With this little pest chaser they do not come in. They dont want too ! After I started using this thing the little verman had left. Not a sign of them. No more clattering noise in the walls or ceiling at 4AM. No more of the little pellet or big pellet droppings. No more damage to the house.
After trying them at my own house I have used them elsewhere with the same good results.
One thing I did do was use more than what the directions suggested. Overdid it a little cause like I said before, I was desperate to be rid of them. The things work.

Alan (California Radiant) Forbes

This guy nibbled one too many wires. Chewed through the insulation on a hot leg of knob and tube and then climbed over the wire to connect the circuit. It was a quick death.

Leonard

Think you just have to seal ALL openings to house.

My cousin had mice in cellar, I told her to seal up openings to the house, she had some rotted wood over outdoor bulkhead steps to cellar. She did and mice were gone.

In my house I notice 1/2 inch gaps under door frame to garage and celler steps. I'll have to seal those.

I adopted some semi- feral cats and ran a power cord under overhead door to outdoor heated cat houses all winter, overhead door was open ~ 1/2 inch. Later found I had mice in attic. Read they can crawl thru openings size of a dime. Guesing they crawled under overhead door, and got into wall thru 1/2 inch shrink gaps between wood boards on wall, and climbed thru wall into unfinished attic. I once heard them crawling up thru the wall.

Another time a bat got in crevice 6ft off ground and I listened to him crawl down garage wall, and along 50 feet!!! of wall in cellar. I sealed that opening. And this is a fairly well built house , 60 years old.

That eating thru power cable is scarry

I put one of those mice traps in attic, it worked pretty well, less scratching at walls. Was one of those pro types, trap them live. Peanut butter on a trigger pad, they walk in open ended tunnel to get the food, their weight on pad triggers assembly to QUICKLY spin flinging them into a side chamber. You wind it up like a clock. Nice thing about that is no corpses rotting in attic, stinking up the place.

Intplm.

Seems you can never find all the holes no matter how hard you try. The critters find more places than you can find. I used to bait with d-con. That worked but found the dead guys all over , and plenty of stored d-con piled in different places.
The "victor pestchaser" keeps the rodents away. They didn't even come in the house. They had to stay away because they could not stand the ultrasonic sound.

ethicalpaul

Aww, the little guy just wanted to take a shower!

Larry Weingarten

Well, Had he been a true "Plumb-Rat", he woulda installed a chrome shutoff valve and showerhead, along with a towel bar. This had to be a standard "Dirty Rat"... Nice rodentart!

Yours, Larry

archibald tuttle

jumping on one of these pest threads that is still open. i have not had the problem with mice (maybe they have too much else to eat) but squirrels chewed through pex and created a shower in the middle of the living room in one house. Fortunately, that was the basement and we worked to exclude the squirrels but they are wiley **** and you kinda get to feel like bill murray in caddyshack.

has anyone ever seen a manufacturer armor pex tubing in the manner of MC cable. Seems to me that is a mature technology that would make more sense than sliding pex into conduits. Still have small areas of exposure at the end of runs but i'm replacing massive old copper hot water lines w 1/2" and 3/8" home runs so I can keep the connections in limited accessible locations and thus cut my possible rodent damage down to manageable size if the pipe were sold with protective covering. hey, you never know, maybe that would make the folks in chicago happy and they could join the plastics generation.

brian

Jamie Hall

All this is why I always use armored electrical cable... I don't mind getting wet (I've used PEX here and there) but I do mind electrical fires...

ChrisJ

> @Jamie Hall said:
> All this is why I always use armored electrical cable... I don't mind getting wet (I've used PEX here and there) but I do mind electrical fires...

They tend to interrupt the flow of your day?

ratio

There's flex aka FMC aka Greenfield, available in sizes from ³/₈ through 4". At least the smaller sizes are available in steel as well as aluminum.

Jamie Hall

ChrisJ said:

> @Jamie Hall said:

> All this is why I always use armored electrical cable... I don't mind getting wet (I've used PEX here and there) but I do mind electrical fires...



They tend to interrupt the flow of your day?

Something like that.

archibald tuttle

ratio said:

There's flex aka FMC aka Greenfield, available in sizes from ³/₈ through 4". At least the smaller sizes are available in steel as well as aluminum.

right but try inserting pex through a 40 foot long closely sized piece. i long since gave up on greenfield in favor of preformed MC cable. I'm betting that the mature process for manufacturing cable in this manner could be as readily applied to pex as to several runs of thhn. I've got 6 months before this job so i'm trying to stir the pot. Maybe it won't hit the market by then and i would have access to replace this although it would be an HR nightmare with tenants were it that to come at a time of some squirrel's chosing and not my own. @Jamie Hall It is the very lessons of NM wire that has been chewed that leads me to consider this. I have one building that is kind of half built project where this has been a nightmare and a i kick myself for not having used MC. Of course at the time I didn't see this as a potential unfinished symphony, but life has a way of throwing curve balls. And MC was not prevalant and the roto-split, although invented in 1973 was not widely deseminated until after I wired this project.

I wonder if lucien ducret's wife asked him why he had to solve the industry's problem when he was just a rewiring one building. I get that question all the time. Like why did I just spend a half an hour on the phone with a brass fitting company I found at AHR to see if I could buy 1 and 1/2" cast brass hex bushings before they were drilled in the center so I could drill and tap a 1/2" outlet eccentrically for radiator return bushing. (I'm currently doing that with stainless hex plugs but the machining of the stainless is a pain in the **** and nobody makes a brass hex plug over 1").

Well, i don't think i'm ready to start a process manufacturing line wrapping pex for armored applications. But I can see the caution implicit with field engineers who have experienced pest damage so I wonder who in the pex pipe manufacturing industry might be thinking about this?

I suppose i could come up with some clever way to vacuum a lead line through 40' of greenfield and pull the pex into place. I'll have to see what internal diameters are available. that is the other thing, the manufactured armored cable is generally a little more chase efficient because it is just the right size but maybe 3/4" nom greenfield would work.

george_42

25 years ago my house burned down while we were away , the fire inspector found a place where mice had chewed through the wires and shorted them out. House was a total loss but no one hurt. Glad I had GOOD insurance. George

Larry Weingarten

Hi, I use standard grey PVC conduit to shield PEX in ratty living rooms, like attic or crawlspaces. It seems that going bigger, like 3/4" or so, makes it hard for the rat to get his or her teeth around it. Also, being smooth wall inside makes it easy to pull or push PEX through. Maybe larger diameter poly-pipe would work?

Yours, Larry

archibald tuttle

did find this though. it will take experimentation to see how much length of 1/2" pipe i could slide through the 5/8" internal diameter. and i wonder if its possible to get 'straight' 1/2" pipe in lengths longer than 20'. 30 or 40 would surely be a help with this. its funny, would need to be coiled for shipping but if its only a day in shipment it wouldn't really have developed a shape memory by then in my experience.

brian

Leonard

Makes me wonder if could spray some chemical on plastic pipe that would keep mice/rats from chewing it. On farms they have something bitter you can spray on things so animals/horses don't chew things. I accidentally found isopropyl alcohol was bitter, after cleaned my glasses with it I eat some food and licked my fingers. No idea how long it lasts though.

rick in Alaska

archibald tuttle said:

did find this though. it will take experimentation to see how much length of 1/2" pipe i could slide through the 5/8" internal diameter. and i wonder if its possible to get 'straight' 1/2" pipe in lengths longer than 20'. 30 or 40 would surely be a help with this. its funny, would need to be coiled for shipping but if its only a day in shipment it wouldn't really have developed a shape memory by then in my experience.

brian

Since the 1/2" pex is 5/8 od, you are not going to get it through the 5/8 tubing. You would have to go through the 3/4 tubing.
Rick

BillyO

cheaper solution would be to hire an exterminator

ChrisJ

BillyO said:

cheaper solution would be to hire an exterminator

Yeah,
For some reason I see no need for wiring or plumbing to be compatible with rodents that use your house as a toilet.................

Best to keep them out and if they some how get in, get them out immediately.

Jamie Hall

Good luck on keeping the little beggars out. A very modern house, maybe. An older one? Not a hope. The stuff to which @Leonard refers works a treat for cows and horses, and really does keep them from chewing on fences, wall studs, whatever... but so far as I know doesn't seem to phase rodents in the slightest.

There are -- also for farms -- some remarkably lethal poison baits. They do work, but I wouldn't dream of using them where pets or other desirable predators (like birds) can get hold of the carcasses, never mind children etc.

ChrisJ

> @Jamie Hall said:
> Good luck on keeping the little beggars out. A very modern house, maybe. An older one? Not a hope. The stuff to which @Leonard refers works a treat for cows and horses, and really does keep them from chewing on fences, wall studs, whatever... but so far as I know doesn't seem to phase rodents in the slightest.
>
> There are -- also for farms -- some remarkably lethal poison baits. They do work, but I wouldn't dream of using them where pets or other desirable predators (like birds) can get hold of the carcasses, never mind children etc.

Do you feel my house is modern.

archibald tuttle

@ChrisJ and @BillyO
can't argue a preference for less rodents in the world or in the house. these days when i see a squirrel in the road i try to run it over, but there is a limit to what can be accomplished. no question the worst consequential damage i've experienced is one of the those life time projects that i did finish the exterior to exclude rodents. But the actual pex damage and consequent use by a squirrel of one of our buildings as a shower was before anyone knew we had a problem.

so I'm just trying not to compound the headaches rather than accept permanent cohabitation, esp. squirrels and rats, mice I kind of have a detente. IF they venture into the living space they get killed in my traps, but if they keep to themselves and i clip the procreation rate with my trapping i can't be bothered going all bill murray caddyshack about it.

still interested though if anybody has ever seen stick pex in lengths longer than 20'. I am always wanting this anyone for other reasons. Maybe i don't understand the material physics well enough, but i don't see why there couldn't be 30 or 40 foot lengths given the length of the trailers its delivered in, and my experience is that these just in time distributors could coil it lightly for shipment. you get it in a day and uncoil it and it won't have the same tightly coiled memory that the precoiled stock does.

brian

Jamie Hall

No, @ChrisJ , I do not think your house is modern! Delightful, yes. Modern... not really. You might be able to seal it up tight enough though...

Gsmith

PEX is available in industry in spools or coils much much longer than 20 feet, but I doubt you can get it at most supply shops, but check. On one project we got 1,800 feet of 2" on a single spool.

mikemac52

Sealed up my old house best I could, traps and poison to catch the ones that penetrated anyway, and was betrayed from the inside.

Water line to the fridge was chewed through and came home to water pouring out of pantry/ rear entrance.


Changed to copper.





He felt sorry...

Leonard

Few years ago 2 outdoor semi-feral cats adopted me. They didn't want to be in house with door closed. Winter was coming, so I put a pair of syrofoam boxes outside with electric heating pads to keep them warm. worked great.

Never had mice in house.......But to power heater pads I ran one of those orange extenstion cords under overhead door. So door had a small 3/8 -1/2 inch gap under it. Plenty enough space for mice to get into garage then climb into attic and down thru walls into cellar.
Made a mess eating cellar stored food.

Had one of those pro traps from a commercial building to catch them. You wind it up then as they step in and trigger it , a paddle swoops them into next chamber , and it's ready for next mouse. Caught 5-6 in one night. Nice thing it's a live catch trap, no mess. Just dump them into pail of water outside for their "swim" time.

Cats got drove off by a bulley cat so I was able to remove cord from under door that winter. No more mice, 62 year old house.

Supposedly mice can get in thru hole the size of a dime or nickle, got to close up ALL holes that size or larger. Likely larger min size hole for rats.

ChrisJ

> @mikemac52 said:
> Sealed up my old house best I could, traps and poison to catch the ones that penetrated anyway, and was betrayed from the inside.
>
> Water line to the fridge was chewed through and came home to water pouring out of pantry/ rear entrance.
>
>
> Changed to copper.
>
>
>
> (Image)
>
>
> He felt sorry...

I don't have a water line going to my fridge as I feel those are junk.