Put this in the start of yer init.sqs:
cutText ["","black in",9999]
_svol = soundVolume
_mvol = musicVolume
~.1
0 fadeSound 0
0 fadeMusic 0
~.1
;<<Insert house destroying stuff here>>
~<<wait for the houses to get mangled>>
cutText ["","black in",5]
8 fadeSound _svol
8 fadeMusic _svol
This should work
Of course, if you have music playing then you don't want to fade the music volume to 0...
You might need to make something to play on the screen that occupies the player attention for the time it takes to get the houses destroyed, so the wait doesn't get too long...
Oh, and no guarantees granted