Scratching in the walls/ceilings

[Topcat]

Hi. We live in suburbia, west of Brisbane, and we have something in our roof that 'scratches' and 'gnaws' (loudly) at night time. We have set 'mouse traps' and 'rat traps', and 'opossum traps', but we have never caught anything. We even put our two cats up there, for a day, and it did go quiet for a time, but the sounds are back. We have put 'baits' up there, and they are untouched. We have annual inspections for Termites and we have been 'cleared' on that score. (We do have lots of Ghekos, though.) Do cockroaches make a sound like they are chewing wood to splinters?

Has anyone else had this problem? What did it turn out to be? How was the problem resolved?

I'd love to hear from anyone.

Community manager's note: Check out How to deter possums from your roof for expert advice.

[dob80z]

Hi Jason,

Sorry for the delay in replying.

I sort of acquire them from cleaners trolleys (!?!?!) - but Officeworks sells them as well Urinal Deodorant Blocks. Unfortunately only in 4kg buckets for around $55 - so hardly useful unless you live in a possum forest...

Maybe you have a packaging place and/or hospitality shop nearby - they should be able to help you find some.

[Andy_Mann]

@dob80z @Jason

I did a search & came across this precautionary document:

http://www.cleaningshop.com.au/contents/en-us/fresha-toilets-blocks-msds.pdf

It might be an idea to avoid them altogether, or put them in a well secured, wide container with ventilation holes, so that pets or kids can't get to them, or tip it over.

[Kermit]

I've heard the dreaded scratching in an internal wall a few times over the past week. The wall ajoins an external wall and has an air conditioning unit on it so I suspect that's how the dirty rat has got in. The room has a flat roof though so I have no access to the wall cavity. I might just have to try putting bait nearby. 

[Baretta11]

@Kermit,

There would need to be a fairly good sized entry hole for the rat to have got into your walls via the AC.

If the AC is a recent fitout and you are positive about the entry point, you may be able to make the AC fitter address the hole/s that may have been left and unsealed during instalation.

If it's not a new AC, you may need to have someone help with removing it without having to let the gas out if possible and see if you can find the entry point if you suspect that's where it is and steel wool is a great deterent shoved in the hole as rats and mice can't chew through it.

Never underestimate how small a hole needs to be for mouse entry either, less than 1cm will do!!

However, unfortunately, there are so many places that rats or mice can enter, as I found out with my mother's home last year. Trees right bedide the home allow perfect access from the branches to the eaves or roof with my mothers home being inundated by rats for precisely this reason. Also an unsealed manhole under the house/veranda was another access point for my mother's home.

We had to remove and replace a 1/3 of the insulation from urine stains in the roof, as well as vacc the entire ceiling area from droppings and took out countless dead rats after baiting AND we spent an obscene amount of time finding and covering entry spots to avoid a repeat!!

Baiting as you suggested, is an excellent way of keeping the numbers down and you can get the bait blocks that can be nailed up away from pets and the rats can't resist them. If you find them missing completely, like we did initially, then you know you have plenty of rats. Eventually, you end up finding the baits are still there, meaning you have arrested the problem and killed every rat. If you see small chew marks or rounded edges on the baits, that's mice.

All I can suggest from my experience, is never stop baiting in garden sheds, open carports etc...in the roof where there is access and you will never again have a problem.

People think that once they see a dead rat, that's it, jobs done but there is the next generation coming along and you have to be prepared.

Goiod luck.

Cheers,

Barbara

[Andy_Mann]

I had the pleasure of doing a country trip at a place that was amidst a mouse plague. The manger of our accomodation stay, chose baiting to get around the problem, but the living mice were still a problem, & to make it worse, the decomposing ones were a more obnoxious presence. I kid you not, I put after shave on my arms & the pillowcase, yet the stench was overwhelming, that even I struggled to sleep.

[Henno]

Topcat, possums are masters of stealth and are capable of flattening themselves out in order to fit into a gap under a tile on your roof or a cavity in your wall. Do not underestimate these animals.

First port of call is to check you roof for loose tiles (if you have a tiled roof) and overhanging trees in close proximity.

Another thing you should check is if one of your neighbours is feeding them. Worst case scenario ever! They go there to feed and your place to bed down...

The way we fixed the problem was by firstly chopping down the overhanging tree and then sorting out the neighbour who was feeding them (in a nice manner mind you). Trapping and relocating possums is just making it somebody else's problem.

I won't tell you what our third fix for the problem was, but you can import a trap from NZ which deals with the problem in a permanent manner.

[Kermit]

Heard more of the dreaded scratching in the ceiling the last couple of nights. Are our fanged and furry friends more active at this time of year? At least it was in a section of the ceiling that I can access. Looks like I need to get up there and put some bait down. I also spied some telltale rat droppings on the top rail of our side fence. Must be their highway....

[Baretta11]

@Kermit,

Oh goodness, the next generation heh??

It can be so soul destroying getting up in the ceiling and finding this invasion has comenced yet again but my previous suggestion is to never stop baiting!!

Do you remember I mentioned the rat blocks with holes in the centre that allow you to pop them on a nail up high away from domestic pets, they're the best. Buy a bucket from a local animal feed type store, don't think you can get a bucket at the local supermarket.

A store like Landmark, Williams and Jackson, possibly Petstock etc...a place that has rural supplies is the best bet or just look on line.

So far in the new home due to using rodent mesh around the entire perimeter of the bottom plate of the frame, we have no rodents of any description in the roof space, I check it regularly.

My sparkie set up fluro's in my ceiling, three in all and he said you only need to have to access your roof space just once in the pitch black to appreciate lighting and I have to agree it's the best thing ever, was so easy to put the insulation in and do other electrical work during the construction. I also have an attick ladder fitted into the laundry ceiling so access is so, so easy and the light switch is at the top of the ladder, so lucky I have this actually!!

 

[Kermit]

One of the best thing we did in our first home - a really small Victorian cottage - was to install a roof space ladder in the hallway so we could use the attic as storage. Adding lights as well was a really smart idea @Baretta11.

Looks like Bunnings has 1kg buckets of bait blocks which is more than what I need (I hope!!!) - https://www.bunnings.com.au/search/products?q=block%20bait Will have to get some on the weekend.

[Baretta11]

@Kermit,

How silly of me not to realize Bunning's would have it but how simple too ha-ha

As for the lights in the roof, not my idea, it was the sparkies signature trademark he called it.

I simply came home to him swinging from truss to truss like a monkey installing these fluro's but so glad he did it!!

Good luck with your baits.

Cheers,

Barbara