Deonna Zuffa, 43, could face up to three years in state prison when she's sentenced by Alameda County Superior Court Judge Stuart Hing on May 16.
But prosecutor William Denny said Monday that Zuffa's fate will be influenced by a diagnostic study that will be conducted by psychologists at the Central California Women's Facility in Chowchilla.
Hing placed Zuffa in custody and ordered that she be sent to the facility after she entered her plea last Friday.
Denny said that in addition to recommending that Zuffa be sent to state prison for three years, the diagnostic study could recommend that she serve time in the county jail or get outpatient treatment.
He said Zuffa suffered burns on 60% of her body in the blaze at the home at 839 E. Angela St. in Pleasanton at about 10:35 a.m. Dec. 8, 2008, and has been getting treatment for them ever since.
Prosecutors said a notice of foreclosure eviction had been posted on the front door of the family's home shortly before the fire.
Zuffa's husband, Keith Zuffa, and their two sons weren't at home at the time of the fire. Deonna Zuffa was the only person who was injured in the blaze.
Keith Zuffa divorced her after the fire, according to public records.
Deonna Zuffa was arrested in connection with the blaze on Dec. 21, 2010, in Lincoln, where she was living with her parents.
Denny said that in exchange for Zuffa's plea to the arson charge, prosecutors dropped charges that she possessed flammable material with the intent to burn property and that she caused damage to adjacent homes that were damaged in the fire.