The suit says Johnson, 59, a truck driver and West Philadelphia resident, died of problems that resulted from injuries suffered in the building collapse on Market Street near 22nd.
Jeffrey P. Goodman, a lawyer for the firm Saltz Mongeluzzi Barrett & Bendesky, filed the suit for Bonnie Johnson, Danny's wife. They have five adult children.
"For more than three weeks after the collapse, Mr. Johnson was in and out of the hospital suffering from cardiac complications, pulmonary injuries and the crushing of his lower body," Goodman said in a statement. "Medical records and a forensic pathologist have confirmed his death was caused by those injuries in a preventable tragedy."
The estates of the other deceased victims, including Anne Bryan, the daughter of City Treasurer Nancy Winkler, have already sued many of the same parties.
Contractor Griffin Campbell and excavator operator Sean Benschop have been charged with manslaughter. There are no other related criminal cases.
The incident also apparently cost the life of Ronald Wagenhoffer, a city inspector tasked with the demolition project who committed suicide days after the collapse.
The city, although it is not being sued by the victims, was criticized for lax oversight of the demolition and has overhauled its regulations for demolition and construction projects.
On Twitter: @SeanWalshDN