S.C. Code Ann. § 5-25-730: Steam pipes.

No steam pipes shall be placed within two inches of any timber or woodwork unless the timber or woodwork is protected by a metal shield and then the distance shall not be less than one inch. All steam pipes passing through floors and ceilings or laths and plastered partitions shall be protected by a metal tube one inch larger in diameter than the pipe, and the space shall be filled in with mineral wool, asbestos or other incombustible material.