Level 1 alteration: shall comply with the provisions of chapter 6 of the international existing building code. To include the removal and replacement or the covering of existing materials, elements, equipment or fixtures using new materials, elements, equipment or fixtures that serve the same purpose. For interior alterations to renovate an existing 1st and 2nd floor (vacant building). This work activity shall be performed by contractors & sub-contractors licensed by the city of philadelphia. Contact inspector at district office prior to starting work. Separate permits required for plumbing, electric and hvac.