Historic preservation is the act or process of accurately revealing or salvaging the state of a historic building, as it appeared at a specific period in its history, all the while protecting its heritage value. Restoration work may be performed to reverse deterioration, or adjustments made to a building.
Proper historic building preservation aims for a high level of authenticity, where accurate replication of historic materials, as well as techniques, are used as much as possible. Modern techniques are used only in a concealed manner where they will not compromise the historic character of the structure’s appearance. For example, a heritage restoration might encompass the replacement of obsolete heating and cooling systems with newer ones, or the installation of climate controls that never existed at the time of building.