Building restoration describes a particular treatment approach and philosophy within the field of architectural conservation. According to the U.S. Secretary of Interior's standards, "Restoration is said as the act or process of accurately depicting the form, features, and character of a property as it appeared at a particular period of time by means of the removal of features from other periods in its history and reconstruction of missing features from the restoration period. The limited and sensitive upgrading of mechanical, electrical, and plumbing systems and other code-required work to make properties functional is appropriate within a restoration project." In the United States restoration is different from preservation (American English, conservation in British English) by allowing t