How to stop mice entering house from fireplace?

[vanillah]

Hi all!

*old house, mids reno*

I had problem with mice comming from underneath the fireplace 👀 even now in summer.

Initially I just filled the gap with steel wool.... and that was fine till we started using  fireplace last winter and  steel cought fire 🔥 ( suspect that there was a breach of contacts  and short circut

 

  with the fan under .... so we are not doing that again 👀) 

I have seen some  high temp resistant fillers. 

Tell me what do you thing and whats your product recommendation!

Thank you !

[AlanM52]

Hi @vanillah,

All mice need to visit Specsavers that's why the rely heavily on their sense of smell.

Start with things that have smells that mice hate, often to the point where the smell is a sign of danger and they will retreat.

Google with search criteria like 'what smells do mice hate' or similar and one of those should work.

Consider that a short term solution to give you time to arrange for a full inspection of the heater.

I advise not to use the heater until it is inspected by a qualified person and given the all clear.

The best person is a licensed plumber who is registered in the class of Mechanical Services work visit as mentioned here.

Keep in mind the above is likely related to home and contents insurance.

Let us know how it works out for you...

Cheers

[vanillah]

Yeah I have tried all of that..... unfortunately...  not that successful.  Not sure if our outback 🐀 are true adrenalin junkies or just really desperate......  if there is a hole, they will get in. 

So as I am working on fixing massive diy failures of the previous owners..... must say... fire place is one of them. 

Thanks! 

[AlanM52]

With gloves shove Ratsak pellets in there.

Bright light, desk lamp on it's side.

Block off from inside, cut piece off glue trap sheet and shove in there.

Motion activated realistic cat.

(Videos of motion activated cat)

Cheers

[MitchellMc]

There are fireproof products available that are suitable for this situation @vanillah, such as Selleys ready-to-use fireproof cement, which is designed for sealing gaps around fireplaces and can handle high temperatures safely. 

Before sealing anything up, though, it is really important to make sure there are no mice still accessing or living in that space. If you seal the gap while a mouse is inside, you can end up with much bigger problems later, including smells and the need to pull the fireplace apart to remove it. Trapping and removing them first is the safest approach.

You also need to be careful not to block or restrict that grille at the bottom of the fireplace. In many units, this acts as an air intake or part of the convection system, especially if there is a fan underneath. Blocking airflow there can affect how the fireplace operates and may create safety issues. Depending on the exact layout, sealing between the tiles and the fireplace base with fireproof cement may be an option, or fitting a slim aluminium trim at the front could help close the gap without interfering with airflow or internal wiring.

Given that steel wool previously caught fire in this area, I would strongly recommend having a fireplace installer or specialist take a look. They can confirm what that opening is used for, check the wiring and airflow, and suggest a permanent, fire-safe solution that also stops rodents. That way, you know the fix is both effective and safe long-term.

Please let me know if you have any questions.

Mitchell