<photo>Detail of window arches above a rehabilitated storefront;  Link to National Park Service
STANDARDS FOR REHABILITATION AND GUIDELINES FOR REHABILITATING
<photo>significant staircase, Department of Interior, Washington, DC

Identify    Protect    Repair    Replace    Missing feature   Alterations/Additions

Identify, Retain and Preserve

-INTERIOR SPACES-

Recommend
Identifying, retaining, and preserving a floor plan or interior spaces that are important in defining the overall historic character of the building. This includes the size, configuration, proportion, and relationship of rooms and corridors; the relationship of features to spaces; and the spaces themselves such as lobbies, reception halls, entrance halls, double parlors, theaters, auditoriums, and important industrial or commercial spaces.

paired drawings of historic hotel conversion to affordable housing and why it met the Standards for Rehabilitation

The Pacific Hotel, located in downtown Seattle, was constructed in 1916. In conversion from its original use to affordable housing, the hotel rehabilitation successfully utilized the historic floor plan with only minimal changes, as is shown in these before and after plans of the development's east wing. Drawings: NPS files.

Not Recommended
Radically changing a floor plan or interior spaces--including individual rooms--which are important in defining the overall historic character of the building so that, as a result, the character is diminished.

Altering the floor plan by demolishing principal walls and partitions to create a new appearance.

Altering or destroying interior spaces by inserting floors, cutting through floors, lowering ceilings, or adding or removing walls.

Relocating an interior feature such as a staircase so that the historic relationship between features and spaces is altered.

-INTERIOR FEATURES AND FINISHES-

Recommend
Identifying, retaining, and preserving interior features and finishes that are important in defining the overall historic character of the building, including columns, cornices, baseboards, fireplaces and mantels, panelling, light fixtures, hardware, and flooring; and wallpaper, plaster, paint, and finishes such as stencilling, marbling, and graining; and other decorative materials that accent interior features and provide color, texture, and patterning to walls, floors, and ceilings.

photo showing the importance--feature by feature--of a modest entry hall to a historic school

This modest entry hall to a historic school features a utilitarian stair, slender newel post and handrail, paneled door, wood wainscoting, and simple trim define the nature of the space and also emphasize its overall verticality. Dropping the ceiling or even adding a more elaborate newel post and handrail during rehabilitation would change the spatial character of this entry hall and upset the delicate balance of its architectural components. Photo: NPS files.

Not Recommended
Removing or radically changing features and finishes which are important in defining the overall historic character of the building so that, as a result, the character is diminished.

Installing new decorative material that obscures or damages character-defining interior features or finishes.

Removing paint, plaster, or other finishes from historically finished surfaces to create a new appearance (e.g., removing plaster to expose masonry surfaces such as brick walls or a chimney piece).

photo showing inappropriate removal of plaster from perimeter walls during rehabilitation, leaving the brick wall exposed

Plaster has been inappropriately removed from the perimeter walls during rehabilitation, leaving the brick wall exposed. The plaster should have been retained and repaired, as necessary. Photo: NPS files.

Applying paint, plaster, or other finishes to surfaces that have been historically unfinished to create a new appearance.

Stripping paint to bare wood rather than repairing or reapplying grained or marbled finishes to features such as doors and panelling.

Radically changing the type of finish or its color, such as painting a previously varnished wood feature.

Protect and Maintain

Recommend
Protecting and maintaining masonry, wood, and architectural metals which comprise interior features through appropriate surface treatments such as cleaning, rust removal, limited paint removal, and reapplication of protective coating systems.

photo of an office building corridor with its intact and simple detailing, all of which needs to be preserved in rehabilitation

This corridor has glazed walls, oak trim, and marble wainscotting, typical of those found in the late 19th and early 20th century office buildings. Maintaining and preserving corridors that display intact and simple detailing, should be a priority in rehabilitation projects involving commercial buildings. Photo: NPS files.

Protecting interior features and finishes against arson and vandalism before project work begins, erecting protective fencing, boarding-up windows, and installing fire alarm systems that are keyed to local protection agencies.

Protecting interior features such as a staircase, mantel, or decorative finishes and wall coverings against damage during project work by covering them with heavy canvas or plastic sheets.

Installing protective coverings in areas of heavy pedestrian traffic to protect historic features such as wall coverings, parquet flooring and panelling.

Removing damaged or deteriorated paints and finishes to the next sound layer using the gentlest method possible, then repainting or refinishing using compatible paint or other coating systems.

Repainting with colors that are appropriate to the historic building.

Limiting abrasive cleaning methods to certain industrial warehouse buildings where the interior masonry or plaster features do not have distinguishing design, detailing, tooling, or finishes; and where wood features are not finished, molded, beaded, or worked by hand. Abrasive cleaning should only be considered after other, gentler methods have been proven ineffective.

Evaluating the existing condition of materials to determine whether more than protection and maintenance are required, that is, if repairs to interior features and finishes will be necessary.

Not Recommended
Failing to provide adequate protection to materials on a cyclical basis so that deterioration of interior features results.

Permitting entry into historic buildings through unsecured or broken windows and doors so that the interior features and finishes are damaged by exposure to weather or vandalism.

Stripping interiors of features such as woodwork, doors, windows, light fixtures, copper piping, radiators; or of decorative materials.

Failing to provide proper protection of interior features and finishes during work so that they are gouged, scratched, dented, or otherwise damaged.

Failing to take new use patterns into consideration so that interior features and finishes are damaged.

photo of inappropriately painted wood trim in a 19th century house that was historically unpainted

In a rehabilitation project, all the previously unpainted wood trim in the 19th century house was painted white. Because the existing interior trim, with its unpainted natural-colored finish, was such an important feature, painting it white resulted in a dramatic change to the historic character of the house. Photo: NPS files.

Using destructive methods such as propane or butane torches or sandblasting to remove paint or other coatings. These methods can irreversibly damage the historic materials that comprise interior features.

Using new paint colors that are inappropriate to the historic building.

Changing the texture and patina of character-defining features through sandblasting or use of abrasive methods to remove paint, discoloration or plaster. This includes both exposed wood (including structural members) and masonry.

Failing to undertake adequate measures to assure the protection of interior features and finishes.

Repair

Recommend
Repairing interior features and finishes by reinforcing the historic materials. Repair will also generally include the limited replacement in kind--or with compatible substitute material--of those extensively deteriorated or missing parts of repeated features when there are surviving prototypes such as stairs, balustrades, wood panelling, columns; or decorative wall coverings or ornamental tin or plaster ceilings.

photo showing how a severely deteriorated interior space was returned to its original elegance

After rehabilitation, this severely deteriorated space was returned to its original elegance. Plaster was repaired and repainted; scagliola colums were restored to match marble; and missing decorative metalwork was re-installed in front of the windows. Photo: Carol M. Highsmith.

Not Recommended
Replacing an entire interior feature such as a staircase, panelled wall, parquet floor, or cornice; or finish such as a decorative wall covering or ceiling when repair of materials and limited replacement of such parts are appropriate.

Using a substitute material for the replacement part that does not convey the visual appearance of the surviving parts or portions of the interior feature or finish or that is physically or chemically incompatible.

Replace

Recommend
Replacing in kind an entire interior feature or finish that is too deteriorated to repair--if the overall form and detailing are still evident--using the physical evidence as a model for reproduction. Examples could include wainscoting, a tin ceiling, or interior stairs. If using the same kind of material is not technically or economically feasible, then a compatible substitute material may be considered.

before and after photos that show how lead-based paint was carefully removed from a historic house, then surfaces re-painted using a compatible primer and finish coat

Rehabilitating historic dwelling units often includes some level of lead-paint hazard abatement. Whenever lead-base paint begins to peel, chip, craze, or otherwise comes loose (left), it should be removed in a manner that does not damage the historic wood trim and also protects the worker. In this example (right), the deteriorating lead-paint was removed throughout the apartment building and a compatible primer and finish paint applied. Photos: Sharon C. Park, AIA.

Not Recommended
Removing a character-defining feature or finish that is unrepairable and not replacing it; or replacing it with a new feature or finish that does not convey the same visual appearance.

 

The following work is highlighted to indicate that it represents the particularly complex technical or design aspects of Rehabilitation projects and should only be considered after the preservation concerns listed above have been addressed.

Design for the Replacement of Missing Historic Features

Recommend
Designing and installing a new interior feature or finish if the historic feature or finish is completely missing. This could include missing partitions, stairs, elevators, lighting fixtures, and wall coverings; or even entire rooms if all historic spaces, features, and finishes are missing or have been destroyed by inappropriate "renovations." The design may be a restoration based on historical, pictorial, and physical documentation; or be a new design that is compatible with the historic character of the building, district, or neighborhood.

Not Recommended
Creating a false historical appearance because the replaced feature is based on insufficient physical, historical, and pictorial documentation or on information derived from another building.

Introducing a new interior feature or finish that is incompatible with the scale, design, materials, color, and texture of the surviving interior features and finishes.

The following work is highlighted to indicate that it represents the particularly complex technical or design aspects of Rehabilitation projects and should only be considered after the preservation concerns listed above have been addressed.

Alterations/Additions for the New Use

Recommend
Accommodating service functions such as bathrooms, mechanical equipment, and office machines required by the building's new use in secondary spaces such as first floor service areas or on upper floors.

  photos showing how vandalized walls of an old school were successfully rehabilitated as corridors of an apartment for seniors

Vandalized walls of an old school building (top) became pristine halls in an apartment for seniors in this successful rehabilitation project. (bottom). The school corridors, as well as the existing door openings, were preserved, but new fire-rated doors needed to be installed to meet code requirements. Photos: NPS files.

Reusing decorative material or features that have had to be removed during the rehabilitation work including wall and baseboard trim, door molding, panelled doors, and simple wainscoting; and relocating such material or features in areas appropriate to their historic placement.

Installing permanent partitions in secondary spaces; removable partitions that do not destroy the sense of space should be installed when the new use requires the subdivision of character-defining interior space.

Enclosing an interior stairway where required by code so that its character is retained. In many cases, glazed fire-rated walls may be used.

Placing new code-required stairways or elevators in secondary and service areas of the historic building.

Creating an atrium or a light well to provide natural light when required for the new use in a manner that preserves character-defining interior spaces, features, and finishes as well as the structural system.

Adding a new floor if required for the new use in a manner that preserves character-defining structural features, and interior spaces, features, and finishes.

Not Recommended
Dividing rooms, lowering ceilings, and damaging or obscuring character-defining features such as fireplaces, niches, stairways or alcoves, so that a new use can be accommodated in the building.

Discarding historic material when it can be reused within the rehabilitation project or relocating it in historically inappropriate areas.

Installing permanent partitions that damage or obscure character-defining spaces, features, or finishes.

Enclosing an interior stairway with fire-rated construction so that the stairwell space or any character-defining features are destroyed.

Radically changing, damaging, or destroying character-defining spaces, features, or finishes when adding new code-required stairways and elevators.

A dramatic two-story interior space that should have been retained and preserved has been radically changed by inserting a mezzanine. Photo: NPS files.

Destroying character-defining interior spaces, features, or finishes; or damaging the structural system in order to create an atrium or light well.

Inserting a new floor within a building that alters or destroys the fenestration; radically changes a character-defining interior space; or obscures, damages, or destroys decorative detailing.

 

 

-GUIDELINES-

The Approach

Exterior Materials
Masonry
Wood
Architectural Metals

Exterior Features
Roofs
Windows
Entrances + Porches
Storefronts

Interior Features
Structural System Spaces/Features/Finishes
Mechanical Systems

Site

Setting

Special Requirements
Energy Efficiency
New Additions
Accessibility
Health + Safety

The Standards

 

  HISTORICAL OVERVIEW - PRESERVING - rehabilitating - RESTORING - RECONSTRUCTING

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Historical Overview