Secretary of the Interior's Standards for Rehabilitation
The Secretary of the Interior's Standards and Guidelines for the treatment of historic properties were written by the National Park Service and revised in 1990. They are federally mandated to be utilized by federal agencies with designated properties or properties that are officially determined to be eligible for National Register listing by the Colorado State Historic Preservation Office. The guidelines recommend responsible methods and approaches and list treatments that should be avoided.
We have listed the standards for rehabilitation since those are most frequently used by people engaged with History Colorado preservation programs. Please scroll down the page for links to additional information.
- A property shall be used for its historic purpose or be placed in a new use that requires minimal change to the defining characteristics of the building and its site and environment.
- The historic character of a property shall be retained and preserved. The removal of historic materials or alteration of features and spaces that characterize a property shall be avoided.
- Each property shall be recognized as a physical record of its time, place, and use. Changes that create a false sense of historical development, such as adding conjectural features or architectural elements from other buildings, shall not be undertaken.
- Most properties change over time; those changes that have acquired historic significance in their own right shall be retained and preserved.
- Distinctive features, finishes, and construction techniques or examples of craftsmanship that characterize a historic property shall be preserved.
- Deteriorated historic features shall be repaired rather than replaced. Where the severity of deterioration requires replacement of a distinctive feature, the new feature shall match the old in design, color, texture, and other visual qualities and, where possible, materials. Replacement of missing features shall be substantiated by documentary, physical, or pictorial evidence.
- Chemical or physical treatments, such as sandblasting, that cause damage to historic materials shall not be used. The surface cleaning of structures, if appropriate, shall be undertaken using the gentlest means possible.
- Significant archeological resources affected by a project shall be protected and preserved. If such resources must be disturbed, mitigation measures shall be undertaken.
- New additions, exterior alterations, or related new construction shall not destroy historic materials that characterize the property. The new work shall be differentiated from the old and shall be compatible with the massing, size, scale, and architectural features to protect the historic integrity of the property and its environment.
- New additions and adjacent or related new construction shall be undertaken in such a manner that if removed in the future, the essential form and integrity of the historic property and its environment would be unimpaired.
(Download the standards as a PDF)
- Learn about the standards for all four approaches to the treatment of historic properties, including preservation, rehabilitation, restoration and reproduction (PDF)
- Read more examples of how to interpret the standards in The Secretary of the Interior’s Standards for the Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring and Reconstructing Historic Buildings (PDF).