A.
All buildings or structures which are structurally unsafe, insanitary or not provided with adequate egress or which constitute a fire hazard or are otherwise dangerous to human life or which, in relation to existing use, constitute a hazard to safety or health by reason of inadequate maintenance, dilapidation, obsolescence or abandonment are, severally, for the purpose of this chapter, unsafe buildings. All such unsafe buildings are hereby declared to be illegal and shall be abated by repair and rehabilitation or by demolition in accordance with the procedure of this chapter.