Filling large gap temporarily

[Larrythecatforpm]

Having my bathroom done, plumber isn’t back till Friday to fit the shower and finish things off. He’s put in a new waste pipe but had to go through the brick wall (obviously) and it’s left a large hole around the waste pipe directly into the bathroom as he had no expanding foam on him, he’s asked us not to use expanding foam and he’ll do it friday.
Problem is it’s due to rain tomorrow! 🥴

He said I could use tissue but obviously it’s not water proof, any other ideas? Was thinking shoving bin bags in there?

Photo of the offending hole. Or do you guys think it’ll be okay?

Wire wool works pretty well

Plastic bags scrunched up? Unless its driving, horizontal rain it's unlikely to come in. Do your eaves overhang that wall to provide some protection?

Eaves overhang so should be okay, just due a lot of rain tomorrow. I’ll see how it goes and have my plastic bags ready just incase. 😂 Lived with a mouldy bathroom for nine years, not happening again!

I'm surprised he didn't use a core drill to make the hole the correct size. In my opinion filling a hole that size with expanding foam is a bodge. how is he planning to seal the outside?