Mice in garage wall against house wall

[Abrahamsson]

I am going to extend water & sewer lines to a utility sink in the garage from the basement of the house, which is wall-to-wall with it. Yesterday when I removed the particleboard, I noticed that the walls are insulated with mineral wool that lies directly against the house facade. The problem is that there is a small gap of about 3 cm between the house and the garage floor plate/sill where mice seem to have come up and wreaked havoc in the insulation throughout the wall. The studs were wet from mouse urine and there was a lot of droppings.

So how do I fix this? One idea is that if I remove the insulation, they will have nothing to crawl around in, so they at least won't get further up the wall. And there shouldn’t be a need for insulation against the house facade (stucco house made of lightweight concrete)? The gap where they come up between the house plinth and the sill on the garage floor plate might be filled with foam sealant and sealed with an extra board on top of the sill that sits flush against the house?

 

[magnu]

Mice are cunning.
You need to fill with something that can't be gnawed. Foam sealant, I think, is gnawable.

I would have tried to seal it with fine concrete or something similar.
An alternative is to poke down some chicken wire as reinforcement and pour on self-leveling compound. But you have to be careful with the self-leveling compound as it tends to run off. However, a second filling usually doesn't run off.

 

[anders07]

There is fine-mesh metal netting on a roll (20 cm wide) that I have used. Cut a suitable piece and attach it over the gap, or alternatively, press it folded into the gap with a knife.

//Anders