How to seal this hole on the floor?

[NorthernLights811]

I've got this horror under my kitchen sink, and I need to seal it with expanding foam. However the hole is at the back of the wall. I was thinking of laying one layer of foam at the time at the perimeter and then gradually coming in until it's fully sealed, however I'm not sure this will work as the foam might fall at the gap.

The diameter of the hole is not huge, maybe 20cm.

 

[DAZB]

Foam should do the job and i would move the wires out of harms way first and make the first burst of foam a good one so it gets to the rear wall and then back off a little to cover the rest but don't overload it too much as the weight could drag it in. It won't look pretty but it doesn't have to and you can always trim it after if you wish.

 

[Laurieo]

Put some wire wool in the hole then foam. Stops mice eating up through the foam.

 

[NorthernLights811]

Put some wire wool in the hole then foam. Stops mice eating up through the foam.

Anti-mice action is another significant too. Thanks for the suggestion. I heard they'd even eat through the wire wool.

 

[Laurieo]

If they eat the wire wool you can catch them with a magnet .

 

[NorthernLights811]

If they eat the wire wool you can catch them with a magnet .