During a news conference in Center City on Wednesday, City Controller Christy Brady said there are approximately 120 imminently dangerous (ID) properties waiting for demolitions or repairs.
At least 4,000 properties are classified as unsafe, she said.
The investigation found that the Department of Licenses and Inspections (L&I) only has 15 inspectors, noting that the department is "unable to reinspect imminently dangerous properties every 10 days due to lack of resources."
That's not enough to keep up with the demand and oversight of the properties, according to Brady.
Several investigations were launched following a deadly building collapse at 22nd and Market streets in June 2013, according to the city controller's office. The collapse killed six people and injured 14 others.
The reviews, along with current investigations aim to assess L&I's ability to meet public safety standards regarding demolitions and construction repairs of unsafe and ID properties.
The Controller's Office is calling on L&I to implement a system to collect demolition costs from private property owners.
"On the average, residential demolition costs upward of $30,000, but the city only recovers about 3%, leaving taxpayers on the hook to pay millions of dollars," she said.
The Controller's Officer also said the eCLIPSE database L&I uses does not designate priority levels of structural deficiencies for demolition and cannot produce a complete listing of all imminently dangerous properties.
Brady recommends the city launch a recruitment office to hire additional inspectors, as well as establish a tracking system that should include the stages of imminently dangerous properties for priority.