Protecting cables from mice

[deko]

Hello all,

I'd like to know of practical ways to protect the electric cable runs in a domestic property. So for the sake of this discussion, let's assume:

- terraced house
- wooden joists for floors
- current installation is T+E
- experiment confined to 1 room on first floor
- resident mouse in room will eat pvc if he sees it
- cable must be protected through joist (from mouse gnawing)
- new wiring will be joined to T+E outside of this controlled room (i.e. not taken back to CU)

Here are my thoughts so far:

1. Use steel conduit (probably not possible without major upheval)
2. Use flexible steel conduit (T+E or singles?)
3. Use pyro cable (realistic?)
4. Use swa cable (realistic?)

Any input would be greatly appreciated.
Thanks
d.

 

[rjm2k]

Mouse trap?

 

[bernardgreen]

Hungry cat

 

[riveralt]

As above, but really you need to prevent the mice entering in the first place.

 

[JohnW2]

1. Use steel conduit (probably not possible without major upheval)
2. Use flexible steel conduit (T+E or singles?)
3. Use pyro cable (realistic?)
4. Use swa cable (realistic?)

I wouldn't be confident that pyro would be rodent proof, but the others would probably be. However, as has been suggested, removing the rodent(s) might be a more realistic solution, because they can be a pain, and not only in relation to cables (any plastic water pipes? ):

Untitled

• JohnW2
• 24 Nov 2012
• 7

Kind Regards, John

 

[Taylortwocities]

Try as you might, the little devils get everywhere.

Heres a live one in a dangerous place View media item 67144

and one that nibbled one too many. Note that it has managed to get INSIDE the consumer unit!

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• Taylortwocities
• 2 Oct 2013
• 1

 

[deko]

As above, but really you need to prevent the mice entering in the first place.

In the ideal house that would be my prefered solution. But in this terraced house it's an impossibilty.

I would however like to limit their movements around the house.
Currently I see the tell-tale grease marks on some of the cables which pass though the joists. If I seal the gaps in these joist with romax sealent or copper mesh, I suspect they'll only chew the pvc on the cables to get through.

If TTC could tell me how he got the mouse in the photo to pose for a picture, I might be able to get a mugshot of it. Then I could paste up a wanted poster, see if any of the local cats are interested in a bit of bounty hunting

 

[Taylortwocities]

Here's a better one

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• Taylortwocities
• 12 Apr 2012
• 6

Most of the cats I've met are, well, scaredycats

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• Taylortwocities
• 24 Jul 2009
• 5

 

[JohnW2]

Currently I see the tell-tale grease marks on some of the cables which pass though the joists. If I seal the gaps in these joist with romax sealent or copper mesh, I suspect they'll only chew the pvc on the cables to get through.

IME, they do, indeed, most commonly chew on cables in the vicinty of where they go through holes in joists, studs, floorboards or whatever, presumably in an attempt to make the hole big enogh for them to squeeze through. If you sealed the cables into the holes in such a manner that it was no loger obvious that there was a hole through the wood, they might well not be bright enough to realise that there is a potential hole for them to enlarge.

You would, of course, have to make sure that your sealing of the holes didn't affect the current-carrying capacity of the cable too much (and I'm not sure that 'sealed into wood' is one of the standard installation methods one can look up!)

Kind Regards, John

 

[deko]

Here's a better one

Untitled

• Taylortwocities
• 12 Apr 2012
• 6

Starting to wonder if TTC is a mouse whisperer?

You would, of course, have to make sure that your sealing of the holes didn't affect the current-carrying capacity of the cable too much (and I'm not sure that 'sealed into wood' is one of the standard installation methods one can look up!)

If I rerouted the cables so that each one passed through it's own, barely big enough, hole in the joist, and then sealed off the older holes do you think they would still try to chew through the new routes? Would this realistically affect the current-carrying capacity of the cable? In a 3" joist.

 

[riveralt]

If I rerouted the cables so that each one passed through it's own, barely big enough, hole in the joist, and then sealed off the older holes do you think they would still try to chew through the new routes? Would this realistically affect the current-carrying capacity of the cable? In a 3" joist.

I thought mice were drawn to the currants (sic). rather than the wood.

 

[deko]

I thought mice were drawn to the currants (sic). rather than the wood.

Lol river!
Should've have seen that one coming!

 

[riveralt]

I once read an article about the problems of electrically minded mice in the usa.
One solution, which may help you, was to fill the whole with brillo pads - apparently the mice are but off by the soap smell and don't like to chew the pad itself.

 

[footprints]

Aww but he's so cute!

I'm afraid they will gnaw cables even if they are not in their way. We had pet rats we used to allow out for a run around, but had to keep them away from cables, our video and TV leads got shorter and shorter as we had to cut off the chewed bits! They just love PVC!

My daughter had sucess with the audio deterrants you plug in the mains when she had mice in the kitchen. Sorry to say traps etc are the only real solution. Afraid the only protection that will work is steel conduit.

I remember being told that the only way to stop rats gnawing through cement blocking an old soil pipe was to cement a tight fitting glass jar in the hole rodents can't gnaw through that!

 

[JohnW2]

You would, of course, have to make sure that your sealing of the holes didn't affect the current-carrying capacity of the cable too much (and I'm not sure that 'sealed into wood' is one of the standard installation methods one can look up!)

If I rerouted the cables so that each one passed through it's own, barely big enough, hole in the joist, and then sealed off the older holes do you think they would still try to chew through the new routes?

Well, my personal (greater than I would have hoped for!) experience of damage by rodents (more often rats than mice) to underfloor cables is that it has nearly always been in the vicinity of passage of a cable through wood, seemingly in an attempt to make the hole through the wood big enough to pass through. In that situation then I would expect/hope that doing as you say would largely deter them. However, as you will have seen, others have had different experiences, with rodents chewing wires 'out in the open', so I don't know how complete a solution it would be for you. Is your experience that they mainly attack cables where they pass through holes in wood?

Would this realistically affect the current-carrying capacity of the cable? In a 3" joist.

'Realistically' and 'significantly'? In my personal opinion, no. As for regulations, even a 3" run of cable whose current-carrying-capacity has been reduced by its installation method theoretically reduces the notional CCC of the whole cable (although this very often is 'overlooked') - although, as I said, whether 'sealed into wood' does reduce it, I'm not at all sure, anyway. Personally, I would not worry about this at all, but I thought I should bring the potential/possible regulatory issue to your attention. Others may have an opinion, hopefully to reassure you.

Kind Regards, John