The Fire Marshal responded to the scene and firefighters were able to put out the fire.
District Judge Steve Lachman is expected to announce on Monday a decision on which, if any, charges will be held over for trial.
The 12 defendants who are the subject of this week's preliminary hearing are not alleged to have taken part in the planning and execution of the gauntlet, but rather, prosecutors contend, forced alcohol on Piazza and other pledges during the party that followed.
Out of the 14 currently suspended chapters, Alpha Sigma Alpha's loss of recognition is the longest active one.
"I'm confident that once this case makes it to a jury, we will obtain justice for the Piazza family."
The suspension stems from a report made in March to the Office of Student Conduct about new member hazing.