R4503.1 General.Repairs shall comply with the applicable provisions of the code for new construction or as permitted by this section. Work on undamaged components that is necessary for the required repair of damaged components shall be considered part of the repair and shall not be subject to requirements for alterations.

R4503.2 Materials. Materials used during repairs shall comply with this section.

R4503.2.1 New and replacement materials. Except as otherwise required or permitted by this code, materials permitted by this code for new construction, shall be used. Like materials shall be permitted for repairs, provided that unsafe conditions are not created. Hazardous materials shall not be used where this code does not permit their use in buildings of similar occupancy, purpose, and location.

R4503.2.2 Existing materials. Materials already in use in a building in compliance with requirements or approvals in effect at the time of their erection or installation shall be permitted to remain in use unless determined by the building official to be unsafe.

R4503.2.3 Plumbing materials and supplies. The following plumbing materials and supplies shall not be used:

1. All-purpose solvent cement, unless listed for the specific application.

2. Flexible traps and tailpieces, unless listed for the specific application.

3. Solder having more than 0.2-percent lead in the repair of potable water systems.

R4503.3 Water closets. Where any water closet is replaced with a newly manufactured water closet, the replacement water closet shall comply with the requirements of Uniform Plumbing Code Section 411.

R4503.4 Structural. Repaired structural elements and systems shall comply with Section R102.7.1 and the structural provisions of this chapter.

R4503.5 Demolition and replacement. Where a building or structure is effectively demolished by damage or where the intended method of repair is demolition and replacement, the replaced building, including its replaced foundation, shall comply with requirements for new construction in the International Residential Code.