III. Historic Properties
Knowledge about historic properties in your neighborhood and community is very important in disaster planning. The first step in planning for their protection is to identify them.
3.2 Historic Building Identification
Survey all areas of the city, town, township or county that contain buildings over 50 years old. The survey will provide a written and photographic data base to be utilized to determine properties that are eligible for the National Register of Historic Places. The State Historic Preservation Office (SHPO) can provide information on conducting surveys of historic buildings.
Determine which properties are eligible for the National Register of Historic Places. Knowing whether properties are eligible for or listed on the National Register prior to a disaster can help speed the process of obtaining assistance for historic buildings after a disaster occurs and will help prioritize technical assistance efforts.
Locate all National Register listed and eligible properties on street maps with addresses for use by disaster assistance teams during and after a disaster. If the community has a local Historic Preservation Commission, locally designated properties should also be located on the street map of historic properties.
3.3 Historic Building Documentation
Take exterior and interior photographs of your historic property to document the building and important details, and key them to a diagrammatic floor plan of the building. Prepare drawings of your property including floor plans, and exterior and interior elevations. The level of detail of these drawings will depend upon your budget and the complexity of your property. Inventory all important pieces of furniture and equipment that are in the building. Store documentation of your historic property in another location for safekeeping. A sample form for documentation of your historic property is included in the attachments section of the plan.
3.4 Historic Building Materials
Wood: Since Minnesota was a major location of the great Pine forests that were heavily logged in the late 19th and early 20th century, wood was a major building material for buildings during that time period. Many historic residential and farm buildings are constructed completely of wood, and are generally light frame instead of timber frame buildings. Many other residential, public, industrial and commercial buildings utilize wood in the floor and roof structures. Wood was also used extensively for windows, doors, floors, interior and exterior trim, and wood roof shingles.
Masonry: Minnesota and Wisconsin are rich in natural building stone that was used extensively in historic buildings. Native stone quarries include Cold Spring granite, Kasota limestone, and Apostle Islands sandstone. Many buildings were also constructed with less durable locally available stone. Local clay was used for brick manufacture in many historic Minnesota buildings from the earliest time of settlement. Other forms of clay masonry include glazed and unglazed terra cotta, and molded brick. Masonry was commonly used for exterior and interior structural walls to create a more permanent fire-proof building. Often masonry replaced earlier wood structures that were destroyed by fire or not constructed for the long term. Slate and clay tiles were used for roofing in more prominent residences and public buildings.
Metal: Cast iron was mass produced for structural members to improve fire resistance and was also used for decorative elements such as railings and fences. Fire protected steel structural members replaced cast iron in the late 19th century. Copper, tin or lead coated steel were commonly used for roofing, flashing, commercial building fronts and ceilings.
Concrete: Concrete was utilized for structural building frames that were required to be fire proof. Concrete was also utilized for floor structures, exterior retaining walls and paving. Concrete was also cast in molds for decorative trim pieces as a substitute for natural stone known as "cast stone".
3.5 Archaeological Properties
Archaeological properties present very different issues for disaster management than historic buildings. Usually disaster damage to these sites do not cause a threat to life safety. However, these properties are important historic resources and require disaster relief planning. A Disaster Plan for Archaeological Properties in Minnesota is available by contacting the SHPO.