Public Buildings Renewal Act of 2021 This bill allows tax-exempt financing of certain government-owned buildings by expanding the definition of exempt facility bond to include bonds used for qualified government buildings. A qualified government building is a government-owned building or facility that consists of one or more of the following an elementary or secondary school; facilities of a state college or university used for educational purposes; a public library; a court; hospital, health care, laboratory, or research facilities; public safety facilities; or offices for government employees. The bill excludes buildings or facilities that include specified recreational equipment or are used for the primary purpose of providing retail food and beverage services, recreation, or entertainment. The bill establishes (1) a $5 billion limit on the amount of tax-exempt financing which may be provided for government buildings, and (2) procedures for allocating and applying for the financing of a building, including a certification that the project owner will use reasonable efforts to ensure against job losses. The bill also allows an exemption from the volume cap for private activity bonds used to finance government buildings.