It sounds like monsters on the roof!

The people in the flat above ours have bought a treadmill. We found out at about 8:30 this evening, when we started to try to put TB to bed and it sounded like the ceiling aboive his bed was about to cave in. Needless to say, Yuri went to complain.

I asked TB what 'that noise [sounded] like'. He said 'it sounds like monsters on the roof'.