Placing functions and services required for the
new use in non-character-defining interior spaces rather
than constructing a new addition.
Constructing a new addition so that there is the
least possible loss of historic materials and so that
character-defining features are not obscured, damaged,
This downtown Chicago library was
expanded in 1981 when additional space was required
with light and humidity control for the rare book
collection. The compatible 10-story wing was linked
to the historic block on side and rear elevations.
Its simple design is compatible with the historic
form, features, and detailing; old and new are
clearly differentiated. Photo: Dave Clifton.
Designing a new addition in a manner that makes
clear what is historic and what is new.
Considering the design for an attached exterior
addition in terms of its relationship to the historic
building as well as the historic district or neighborhood.
Design for the new work may be contemporary or may reference
design motifs from the historic building. In either
case, it should always be clearly differentiated from
the historic building and be compatible in terms of
mass, materials, relationship of solids to voids, and
As part of this rehabilitation, two historic buildings were successfully joined by a new addition.
The small glass connector between the two buildings (see photo, right) is appropriately
set back. Photo: Martha L. Werenfels, AIA.
Placing a new addition on a non-character-defining
elevation and limiting the size and scale in relationship
to the historic building.
Designing a rooftop addition when required for the
new use, that is set back from the wall plane and as
inconspicuous as possible when viewed from the street.
Expanding the size of the historic building by constructing
a new addition when the new use could be met by altering
non-character-defining interior spaces.
Attaching a new addition so that the character-defining
features of the historic building are obscured, damaged,
Duplicating the exact form, material, style, and detailing
of the historic building in a new addition so that the
new work appears to be part of the historic building.Imitating
a historic style or period of architecture in a new
This highly visible new rooftop addition appears
to be part of the historic building because of
its replicative design and historicized detailing,
such as the arched windows. This approach does
not meet the Standards for Rehabilitation. Photo:
Designing and constructing new additions that result
in the diminution or loss of the historic character
of the resource, including its design, materials, workmanship,
location, or setting.
Designing a new addition that obscures, damages, or
destroys character-defining features of the historic
Constructing a rooftop addition so that the historic
appearance of the building is radically changed.