Try to isolate the space with plastic from floor to ceiling. Tape around.
Buy a sledgehammer.
Think back to your unjust math teacher or similar.
A little while later, the problem is solved
There are undoubtedly more sophisticated methods.
But sometimes there's no need to complicate things either.
Addition:
When I did something similar, I drilled a few holes with a hammer drill to get through somewhere. Then you can use the sledgehammer.