The provisions of Section C501 of IECC-CE are adopted by reference with the following modifications:
1. Revise Sections C501.1 and C501.1.1 to read:
"C501.1 Scope.
The provisions of this chapter shall control additions, alterations, repairs, and changes of occupancy to and relocation of existing buildings.
C501.1.1 Existing buildings.
Except as specified in this chapter, this code shall not be used to require the removal, alteration or abandonment of, nor prevent the continued use and maintenance of, an existing building or building system lawfully in existence at the time of adoption of this code."
2. Revise Section C501.2 to read:
"C501.2 Compliance.
Additions, alterations, repairs, and changes of occupancy to or relocation of existing buildings shall comply with Sections C502, C503, C504 and C505 of this code, as applicable, and with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in the other Chicago Construction Codes. Alterations where unconditioned or low-energy space is changed to conditioned space shall comply with Section C502.
Exception: Additions, alterations, repairs or changes of occupancy complying with ANSI/ASHRAE/IESNA 90.1."
3. Revise Section C501.3 to read:
"Devices and systems required by this code shall be maintained in conformance to the code edition under which they were installed. The requirements of this chapter shall not provide the basis for removal or abrogation of energy conservation, fire protection or safety systems and devices in existing buildings."
4. Revise Section C501.4 by replacing each "permitted" with "allowed."
5. Revise Section C501.5 to read:
"Provisions of this code relating to the repair, alteration, relocation and change of occupancy of existing buildings shall not be mandatory for historic buildings provided that a report has been submitted to the building official and signed by a registered design professional demonstrating that compliance with that provision would threaten, degrade or destroy the historic form, fabric or function of the historic building."