Minutes for CFA Meeting — 17 March 2011

The meeting was convened in the Commission of Fine Arts offices in the National Building Museum, 401 F Street, NW, Washington, D.C. 20001, at 10:10 a.m.

Members present:
Hon. Earl A. Powell, Chairman
Hon. Michael McKinnell
Hon. Elizabeth Plater-Zyberk
Hon. Witold Rybczynski

Staff present:
Thomas E. Luebke, Secretary
Frederick J. Lindstrom, Assistant Secretary
Eve Barsoum
Sarah Batcheler
Kay Fanning
Mary Konsoulis
Jose Martinez
Susan Raposa
Tony Simon

I. Administration

A. Approval of the minutes of the 17 February meeting. Mr. Luebke reported that the minutes of the February meeting were circulated to the Commission members in advance. The Commission approved the minutes upon a motion by Mr. Powell with second by Mr. McKinnell. Mr. Luebke said that the minutes will be made available on the Commission's website.

B. Dates of next meetings. Mr. Luebke presented the regularly scheduled dates for upcoming Commission meetings: 21 April, 19 May, and 16 June.

C. Announcement of the 2011 Charles Atherton Memorial Lecture on 7 April 2011. Mr. Luebke announced that Jan Gehl, a Danish architect, planner, and author, will deliver the fifth annual Charles Atherton Memorial Lecture on 7 April at the National Building Museum. Mr. Gehl's topic will be the encouragement of walking, bicycling, and sustainability in cities around the world, with particular application to Washington. He noted that the lecture series was established to commemorate the life and legacy of Mr. Atherton, the long-serving Secretary to the Commission.

D. Report on site inspections. Mr. Luebke noted the Commission's two site inspections, both associated with projects on the agenda: the site of the planned National Museum of African American History and Culture at 14th Street and Constitution Avenue, NW, and the retaining wall along North Road at the National Zoological Park adjacent to Rock Creek Park. Chairman Powell suggested discussing the inspections in conjunction with the review of the submissions. (See agenda items II.B.1 and II.B.2.)

Mr. Luebke reported on the status of the National Capital Arts and Cultural Affairs Porgram, a federal grants program that is administered by the Commission for the support of arts-related institutions in Washington. He said that applications for the 2011 grants have been submitted by the 24 institutions that received grants in 2010, as well as by three new applicants. However, the funding for the 2011 program has not yet been authorized by federal appropriation; therefore no further action will be taken on the program until the budget is established.

II. Submissions and Reviews

A. Appendices

Mr. Luebke introduced the three appendices for Commission action. Drafts of the appendices had been circulated to the Commission members in advance of the meeting.

Appendix I – Direct Submission Consent Calendar: Mr. Lindstrom reported the changes to the draft appendix. One project was added for a temporary tennis stadium and festival area at the Southwest Waterfront, submitted by the D.C. government; the recommended action is for approval limited to a two-year duration. The project would be located on the vacant site of a recently demolished restaurant, and will be superseded by the planned permanent redevelopment of the waterfront that was recently presented to the Commission. An additional project was also added to the report of actions previously delegated to the staff: the final design approval for the American Veterans Disabled for Life Memorial. He noted that the staff will continue to review the memorial's inscriptions and artwork as these components of the proposal are finalized. Upon a motion by Ms. Plater-Zyberk, with second by Mr. McKinnell, the Commission approved the revised Direct Submission Consent Calendar.

Appendix II – Shipstead-Luce Act Submissions: Ms. Batcheler reported several changes to the draft appendix. Five projects were removed to allow time for further consultation and are anticipated for resubmission in the next month; these include case numbers SL 11-052, 11-058, 11-059, 11-060, and 11-063. A report has also been added that lists two actions that were previously delegated to the staff: approval of signs at George Washington University and the site modifications at the United Unions Building at 18th Street and New York Avenue, NW. She noted that the approval for the United Unions project excludes the public space along New York Avenue; the staff is requesting further coordination of this area with the streetscape design for other projects planned for this block of New York Avenue. Upon a motion by Ms. Plater-Zyberk with second by Mr. McKinnell, the Commission approved the revised appendix. (See agenda item II.G for an additional Shipstead-Luce Act submission.)

Appendix III – Old Georgetown Act Submissions: Mr. Martinez reported several changes to the draft appendix. Two projects that were listed with unfavorable recommendations have been removed from the appendix at the request of the applicants; these projects are being revised and will be resubmitted for further review by the Old Georgetown Board. The recommendation for another project was changed to be favorable based on the receipt of supplemental drawings that conform to the Board's recommendation (case number OG 11-094). Upon a motion by Ms. Plater-Zyberk with second by Mr. McKinnell, the Commission approved the revised appendix.

B. Smithsonian Institution

1. CFA 17/MAR/11-1, National Museum of African American History and Culture, 14th Street and Constitution Avenue, NW. Revised concept. (Previous: CFA 16/SEP/10-1.) Mr. Luebke introduced the submission for further development of the museum design, incorporating a response to comments from the Commission in September 2010 as well as from ongoing consultations with other review agencies and their staffs. He noted the site inspection the previous afternoon, with key elements of the building and landscape proposals staked out on the site. He said that the submission emphasizes several elements that have been studied carefully during the development of the concept: the landscape design, the entrance porch and plaza, and the detailing of the corona form around the building's upper floors. The landscape design now responds further to the context of the Mall as well as the programmatic needs of the museum, and includes curving paths, freestanding walls, retaining walls, skylights, and a sunken linear courtyard on the east; the museum's security barrier is integrated into the topography and site walls. On the south, the entrance canopy, walkways, and reflecting pool have been developed further, and a roof terrace is included on top of the canopy. The corona has been developed with further studies of its structure, transparency, pattern, and the placement of openings to frame specific views from the museum's interior. He asked Ann Trowbridge of the Smithsonian Institution to begin the presentation.

Ms. Trowbridge acknowledged the contributions of the Commission's staff in the development of the design through numerous consultation meetings. She noted the planned schedule of a subsequent submission in September 2011, with review of the final design in June 2012 and the opening of the museum in 2015. She introduced architect Phil Freelon, the managing principal of the design team of Freelon Adjaye Bond with SmithGroup. Mr. Freelon emphasized the collaboration among the designers on the project team and the careful attention to the comments that have been received, resulting in an improved project. He introduced architect David Adjaye and landscape architect Kathryn Gustafson to present the design.

Mr. Adjaye said that the architectural presentation would include the development of the building's form and particularly its surface treatment. He summarized the previously presented design, with the building sited to align with others along the north side of the Mall. Closer study has shown the varying relationship of the existing buildings to the setback line established by the McMillan Plan, including varied alignments of building walls and site retaining walls. The siting of the proposed museum is toward the northern edge of this range in order to provide ample space on the south side for views of the Washington Monument and a generous landscape extension of the Washington Monument grounds; the siting has changed only slightly since the previous submission. He summarized the height of the building elements in relation to the context, adding that the changes are similarly minimal since the previous submission; the penthouse height has increased slightly to accommodate elevator overruns. He compared the datum heights of the proposal with those of nearby buildings: the top of the corona would be 113 feet above the city's datum, and the top of the penthouse—set back 23 feet from the building's south facade—would be at 129 feet, compared to datum heights of 121 feet at the National Museum of American History and 175 feet at the dome of the National Museum of Natural History.

Mr. Adjaye described the overall massing of the proposed museum, with an upper volume within the corona above a glass base, and with the supporting structure in the building's interior. The supports for the entrance canopy would be important features in defining the building's relationship to the McMillan Plan alignment, with the building shifting to be in front of and behind the guiding setback. The building has shifted approximately five feet to the west, allowing for the creation of a lightwell on the east that provides emergency egress from the extensive below-grade space that is proposed. He indicated the proposed skylights at grade and on the building's penthouse, where they would illuminate the deep office space on the building's top floor.

Mr. Adjaye presented the proposed floor plans for the museum. Much of the mechanical equipment would be placed in a sub-basement level rather than on the roof, allowing for improved treatment of the roof as a visible plane of the building. The concourse level extends southward under the site; its extent on the north has been minimized to allow for adequate areas of landscaping above. The large concourse level would be contained by a flat landscape podium on much of the site; the slope of the surrounding topography would be accommodated with gentle sloping on the north side of the site. He indicated the concourse-level cafeteria, theater, gallery space, back-of-house space, and loading dock with room for turning trucks. Skylights would be provided at the cafeteria and at the gallery space, where a contemplative area would be created with a water feature A newly developed mezzanine level above the concourse would accommodate education and other facilities; he indicated the sunken courtyard that would provide egress. The ground floor would generally be an open space with four circulation cores; the security screening areas for visitors would be toward the corners so that the main central space would be uninterrupted. A void would bring daylight to the concourse level below. Several upper floors would provide gallery space with clear spans between the four cores. The top floor would contain offices; he indicated the recessed covered terrace that is proposed on the south side adjacent to the board room. The roof, still under development, would include photovoltaic panels that could be combined with the saw-tooth skylight system to create a well-organized appearance in combination with the elevator overruns at the cores.

Ms. Gustafson presented the proposed landscape design and the responses to the Commission's previous comments. The double row of street trees along Constitution Avenue would remain, as requested by the Commission. The water area on the north side of the site has been reduced by two-thirds, also in response to the Commission. The proposed mounds have been lowered to avoid obstructing views from Constitution Avenue toward the Washington Monument. The alignment of the perimeter security barrier has been moved away from the sidewalk, as requested by several review agencies. Seating has been included in the northern part of the site to provide outdoor teaching and storytelling areas. On the south side of the site, the shape of the water feature has been refined to improve its relationship with the diagonal approaches to the building's main doors; she noted that the size of the supports for the porch has also been reduced, allowing for improved definition of this entrance space. The curved paths across the site have been refined to relate to the crosswalks, the Washington Monument grounds, and entry to the museum. She said that the groupings of trees are intended to follow the pattern from the Washington Monument grounds, with carefully framed views and the placement of each grouping on a terraced plateau.

Ms. Gustafson described each area of the proposed site design in more detail. On the north side of the site, she indicated the rain garden, the cafeteria skylight, and the open lightwell. Much of this area would be treated as a terrace to address the slope of approximately nine feet across the site, providing a flat base for the building. The curved walks would ascend from Constitution Avenue to this terrace; she indicated the variations in topography to accommodate the desired slope of these walks. She noted the coordination with the below-grade architecture to provide sufficient soil depth for supporting a healthy landscape, and the improved landscape design that results from the slight shifting of the building's location. She described the stormwater management features: a pond that would normally have water that can be used for irrigation, and a rain garden that would receive and absorb occasional overflow water. She said that most of the existing trees would be retained. A flat area of reinforced lawn with large benches would accommodate groups of people. The oculus skylight would provide the below-grade galleries with daylight as well as a view of the Washington Monument; water would flow around the skylight as a visual, auditory, and symbolic feature that is still being developed. Vegetation would be included on the stepped wall of the cafeteria beneath the skylight, contributing to the indoor air quality; she noted that the cafeteria would also be lit through an opening into the museum's glazed lobby, creating a balanced illumination that would not have the character of a typical basement space. She indicated the stepped topography around the skylights that would eliminate the need for guardrails, allowing for uninterrupted views across the landscape toward the Washington Monument.

Ms. Gustafson described the current proposal for the southern portion of the site. The approach to the museum's south entrance is diagonal, and people exiting the museum lobby would have an open view with no security barriers in their direct line of sight. The trapezoidal shape of the proposed water feature on the south would relate to the larger shapes of areas around the Washington Monument; a combination of still and moving water would be used. The lawn area has been extended and would slope into the bench-height perimeter security wall; this area would serve as an amphitheater. The trees would provide dappled light and shaded areas for people to meet. Plantings at the east end of the porch would limit views of the egress stair rising from the sunken east courtyard which is not intended for general public use. The roof of the porch is now proposed to include a green roof as well as an area for visitors to use.

Ms. Gustafson presented the initial palette of plantings and described the overall intent of the landscape proposal. The character of the Washington Monument grounds would be recalled on the museum site through the use of extensive lawn areas and groupings of trees, with a combination of large trees and smaller flowering trees. Evergreen hedges would be used to frame the landscape elements and screen the perimeter security wall. Existing trees would be retained where feasible. Low ground cover would be used on the sloped areas, providing good water absorption with minimal maintenance requirements. Plants would be selected that cleanse chemicals from stormwater. A perennial garden would also be provided, modeled on an existing Smithsonian staff garden.

Mr. Adjaye provided further information about the porch proposal, which he acknowledged is still being developed. He presented historical images of porches as part of the southern U.S. cultural tradition, with the porch serving as an extension of the house's volume to form an outdoor room. The porch form typically provides extensive shading in the summer and ample daylight in the winter; it also frames the views out toward the landscape. The proposed roof form would extend 200 feet with a support at each end, and would be anchored to the building by two pedestrian bridges; the angle of the roof would be complementary to the 17-degree angle used for the corona design. The portion toward the building would be deeper, serving as a beam to support the overall roof; visitors would be able to occupy the area directly above the beam, while the landscaped outer projection of the roof would have a thinner profile. The resulting form would have a "light" character that invites visitors into the museum. He noted that the porch would serve as a transition to the open spaces on the south and west—the directions of greatest summer heat, making the roof's shading especially desirable—and a shaft of light would enter the porch at sunset. The adjacent water feature would provide a cooling effect for the porch as well as visual interest.

Mr. Adjaye described the design of the corona in further detail, emphasizing the role of the corona in both shading the building and framing views from the interior toward the iconic features and vistas of Washington's Monumental Core. The surface would be panelized using modules based on the proportions of the stone blocks that form the pyramidal top of the Washington Monument. Each tier of the corona would be clad in five rows of panels with a staggered vertical alignment. The panels would be perforated screens with a varying ratio of open and solid areas; the perforation pattern has been studied carefully, and the proposal is to develop a modern adaptation of the ornate decorative iron grilles of traditional southern U.S. architecture—particularly in Charleston and New Orleans. He described the analysis of the geometric pattern underlying the leaf design of the historic grilles; the modern adaptation would be repeated across the museum's panels using various degrees of opacity, and larger openings would provide the framed views.

Mr. Adjaye described the studies for the corona's structural system and the impact of alternative systems on the overall size of the building. The width of the building was previously shown as 230 to 235 feet, with the intention to reduce this dimension to 210 feet which is the width previously presented to and approved by the Commission; some of this reduction was to be achieved through a thinner design for the corona structure. He indicated the overall structural form of the building, with the four cores supporting each of the museum's floors; at the top of the building, a large truss system would extend from the cores to support a perimeter truss from which the corona system would be suspended on cables. The result would be a relatively light perimeter structural system to which the perforated panels would be applied; a glazing system with mullions would also be attached to enclose the building. The optimal design for this system would result in an increase of the corona's width to 220 feet. He said that the obstacle to further reduction is the desire to accommodate a cavity for maintenance access within the structure rather than relying on periodic scaffolding on the exterior; the earlier concept anticipated a more solid structural system that would not have needed this cavity. He said that further refinement of the design details may result in a reduction to 215 feet based on minimizing the critical dimensions; reduction beyond this size would require a more significant reconfiguration of the design and may require that the facade elements be hinged to allow maintenance from the exterior, a solution that would be more costly and less aesthetically satisfactory. He noted that the cable suspension system is subject to movement which is restrained by additional cables, creating further complexity for the detailing of the system. He added that the width of 215 feet was used for the on-site staked mockup that was prepared for the Commission, while the renderings depict the width of 220 feet.

The Commission members inspected models of the site and building as well as detailed models of the alternative corona structures. Mr. Rybczynski recalled that the initial competition for the museum design had included accommodation of a slave ship exhibit within the museum; he asked if this continues to be a design element. Lynn Chase of the Smithsonian Institution responded that a search is underway for a ship that could be exhibited; one ship may be located off the coast of Cuba, and a salvage effort is being negotiated with the Cuban government. Mr. Rybczynski asked where this exhibit would be placed. Mr. Adjaye responded that it would be in the concourse-level gallery which could be excavated to the depth needed to accommodate the ship; exhibiting the ship in the upper-level galleries would be problematic due to height constraints.

Mr. McKinnell noted that the drawings depict a rectangular element around the oculus skylight that is not depicted in the site model. Ms. Gustafson responded that this detail is still being developed; the shape, which may be rectangular or circular, would define the transition of water from an outside to inside area. She noted that the site model does not depict the most recent shifting of the building location nor various site features such as benches; Mr. Adjaye added that the curved path has been realigned to be further from the oculus than is depicted on the model.

Mr. Rybczynski asked if the sawtooth profile of the top-floor skylight would be visible as part of the building's roof profile. Mr. Adjaye responded that the skylight would be set within the area defined by the elevator overruns at the four cores and would not be visible from ground level, while acknowledging that this feature might be slightly visible from a distant elevated location such as the Lincoln Memorial.

Ms. Plater-Zyberk noted that the below-grade construction would extend under much of the site and asked about the sufficiency of soil depths to accommodate the proposed trees. Ms. Gustafson responded that the lawn plane is sloped in some areas to meet the perimeter site walls, providing sufficient soil depth, and noted that these details are still being studied but should not be a constraint. She reiterated that the perimeter security barrier would be within the site rather than at the sidewalk, and the visible portions of the barrier wall would provide seating. Ms. Plater-Zyberk suggested consideration of pulling back the below-grade building area from the southern corners of the site to accommodate the proposed trees more easily, noting that the Commission often sees proposals for berms and built-up lawns for the problematic placement of trees above below-grade structures.

Ms. Plater-Zyberk asked if the canopy above the porch would require substantial depth to accommodate the proposed planting, notwithstanding the drawings that depict a thin edge profile. Ms. Gustafson responded that the edge would be finished in metal, and the planted area would be set back from this edge; the proposed sedum planting would need only a shallow soil depth of approximately four inches. Mr. Adjaye emphasized the design goal of a very thin edge for the canopy.

Ms. Plater-Zyberk asked about the position of the corona's glazing in relation to the structure, noting the potential for difficulty in maintenance. Mr. Adjaye confirmed that the glazing would be below the structure, rather than the usual placement above the structure, but he noted that the slope of the glass would provide sufficient drainage; the detailing of the drainage is still being developed. He said that the reason for this configuration is to provide a smooth glass surface on the interior where museum visitors would be in close proximity; the simplicity of the interior surface would help to focus attention on the framed views outward rather than on the complexity of the structural system. He indicated the maintenance access areas from which the glass would be cleaned. Ms. Plater-Zyberk asked about the detailing of the glass; Mr. Adjaye confirmed that some sort of spacers would be provided, using an unconventional detail that is still being developed, with the overall character of a folded glass form. Mr. McKinnell asked about the configuration of the horizontal surfaces; Mr. Adjaye confirmed that the glass horizontal surface would be supplemented by a grating above to provide a walking surface for maintenance.

Mr. McKinnell asked if the sample of perforated screen illustrates the intended density. Mr. Adjaye responded that the sample is approximately 90 percent solid, which may be appropriate for the south facade where extensive solar shading is desired; on the north facade, a density of 60 to 70 percent would be used.

Following the inspection of the models, Chairman Powell commended the design team for an interesting presentation that responds to the Commission's previous comments, describing the proposal as a "fascinating project." Mr. McKinnell agreed, commenting that the project was beautiful at its inception and has since been improving. He offered several recommendations for further study. He suggested that the skylights in the north part of the site be treated as simple holes in the lawn with minimal embellishment, even avoiding the appearance of glass rising above the ground; he acknowledged that the skylight detailing would involve practical constraints. He observed that the south part of the site would likely become a popular place for outdoor performances, particularly due to the slight slope of the ground and the presence of the porch; he encouraged this use and recommended consultation with an acoustic engineer to study the appropriateness of the porch space for such activities. Finally, he acknowledged the basis of the perforated screens in historical precedent with a resulting emphasis on symmetrical patterning, but suggested consideration of a more abstract and interesting facade pattern that could be facilitated with modern computer technology. Mr. Adjaye agreed that the currently proposed pattern places undue emphasis on the center of the facade and said that the pattern is being studied further.

Mr. Rybczynski expressed support for the porch canopy, commenting that it would make this museum unique and give it a relationship to the Mall that is different from other museums and appropriate to modern times. He also supported making the top of the canopy accessible to visitors, commenting that the canopy would therefore become a "living" part of the building rather than just a roof. He supported the configuration of the site walks in relation to the water features and building entrances. However, he said that the moving water could be a distraction and recommended a calm reflecting pool that would allow people to appreciate the other experiences of the site, including the view of the Washington Monument. He commented that the proposed skylights at grade would have an industrial character that is not appropriate for this project and said they should not be readily visible, observing that they are omitted from the site models which show an attractive simple ground plane. He offered the example of skylights at other Mall museums that are screened with parapets. He expressed skepticism about the proposed rain garden, commenting that its placement along Constitution Avenue would clash with the urban fabric; he said that such gardens have become a "fashionable gesture" that is overly used in contemporary landscape designs. Mr. McKinnell supported Mr. Rybczynski's comments.

Ms. Gustafson asked for clarification of the concern with the north side of the site, noting that the proposed water feature is part of the broader concept of symbolically crossing water to reach the museum. Mr. Rybczynski confirmed that his concern is with both the presence of water and the aesthetics of the adjacent rain garden, emphasizing that the naturalistic landscape and water along Constitution Avenue would be out of character with the urban heart of the capital. Ms. Gustafson responded that the intention is to recall the site's past history as a marsh and later a canal; the historical presence of water would be adapted to the modern needs of sustainable urban ecology. The additional symbolism is to recall the crossing of water that is part of the historical experience of African-Americans and of most other American immigrants as well.

Ms. Plater-Zyberk expressed overall support for the project, which she said is evolving in a very interesting way. She expressed surprise at the complexity of the corona design but acknowledged that the project team is working through the details. She supported Mr. McKinnell's recommendation that the skylights have the appearance of simple openings in the ground, which he clarified as a goal of having visitors "be aware of the absence of something rather than the presence of something." Ms. Plater-Zyberk added that the expression of the skylights above grade would result in unexpected three-dimensional forms within the landscape which should be avoided, while acknowledging that this may not be entirely achievable; Mr. Powell commented that elimination of a railing may result in a safety hazard. Ms. Plater-Zyberk emphasized that any visible features at the skylight should be carefully studied; she added that the same concern extends to the design of the walks as they cross above the rain garden, and she agreed with Mr. Rybczynski's skepticism of this feature. She questioned whether the reference to the historical canal would be worthwhile, noting that the reference would not occur at the other buildings along Constitution Avenue; she said that the canal is a past condition, and the site is now clearly urban. She added that the symbolism of crossing water is clear at the front of the building on the south side, and is redundant on the north; eliminating this northern water feature would allow the importance of the south side to be understood more clearly. She said that the water feature on the south may require further detailing to prevent people from falling into it, and this treatment should be developed as soon as possible for inclusion in the drawings and models.

Ms. Plater-Zyberk said that the intended relationship between the ground-floor glazed walls and the corona's metal screen above is unclear; she suggested that the detailing may need to be developed further with a reveal or slanted plane, and observed that the current configuration does not appear resolved. Mr. Adjaye confirmed that this detail is unresolved and said that it is being studied carefully; he noted that part of the difficulty is accommodating the cable system that is part of the corona structure. The design goal is to provide a termination to the metal screen system and then provide a reveal as a transition to the glazed wall. He noted that the ground floor's wall would have two layers of glass; the cavity between them would be approximately 2.5 feet wide. The intended appearance is of the upper floors floating above a glass base; the detailing of the base would therefore place the glazing support toward the interior so that the exterior appearance is frameless. He reiterated that the technical issues are still being resolved.

Mr. McKinnell commented that the building should be beautifully detailed as the architect intends, which will be important to its perception by the public; however, even a trained viewer would be unable to appreciate the difference between an overall building width of 215 or 220 feet. He therefore recommended that the slightly greater building width would be acceptable if it allows the corona to be detailed more satisfactorily; Mr. Powell agreed. Mr. Adjaye responded that this guidance is very important, and the additional width would allow for a much better design of the corona.

Chairman Powell reiterated the Commission's enthusiastic support for the design and its ongoing development. Ms. Plater-Zyberk commented that we are accustomed to seeing the site as an open space, but the previous day's staking out of the proposal resulted in the unexpected sense that the building would be an appropriate addition, and the site feels empty without it. She said that the building will frame the Washington Monument in a new way and anticipated that the result will be "magical." Chairman Powell agreed, commenting that the site inspection was fascinating; he said that the staking out showed the relationship of the building's scale to the Washington Monument and the Mall, and demonstrated that the museum would take its place surprisingly well within the community of other buildings in the area. Ms. Plater-Zyberk said that the siting of this museum on its own green mound is appropriate when seen in the context of the topography along 15th Street as it curves across the Mall; she supported this simple and sympathetic contextual treatment rather than the introduction of an extraneous design, suggesting that this conceptual approach be used when considering other proposed features such as the rain garden.

Upon a motion by Mr. McKinnell with second by Mr. Rybczynski, the Commission approved the revised concept design with the recommendations discussed concerning the detailing and landscape design.

2. CFA 17/MAR/11-2, National Zoological Park, North Road. General Services Building Retaining Wall. Concept. (Previous: CFA 17/FEB/11- 4.) Mr. Lindstrom introduced the proposal to replace a retaining wall on the north side of North Road within the National Zoo, adjacent to the zoo's General Services Building. He noted that the review is a continuation from the previous month's presentation, and the Commission has now inspected the site both from within the National Zoo and from the roads within and across the Rock Creek valley. He asked Ann Trowbridge of the Smithsonian Institution to begin the presentation.

Ms. Trowbridge emphasized the critical importance of the project due to the failing condition of the existing retaining wall; the Smithsonian plans to begin construction of the replacement wall at the start of the next fiscal year in October. She noted the issue of how the retaining wall design relates to the planned future construction of a parking garage in front of it; she acknowledged the desirability of combining these proposals into a single project but emphasized the funding constraints in planning the garage as well as the need to provide a stable retaining wall quickly. She introduced architect Don Pruitt of Quinn Evans Architects to present the design.

Mr. Pruitt summarized the context and siting of the project, as presented the previous month. The existing structure is failing due to lateral loads from the hillside pushing against the General Services Building as well as related water infiltration. The proposed alignment of the retaining wall would be approximately nineteen feet north of the existing edge of North Road in order to accommodate the future addition of a third lane to the road, as envisioned in the master plan for the zoo. He presented views of the site from within and outside the zoo, indicating the very limited visibility of the parking deck on top of the General Services Building during winter conditions; he said that views would be further limited by the proposed vegetation, and the retaining wall would be only minimally visible above the parking deck. He noted that the 1970s design of the General Services Building included a second phase for the addition of the parking garage above, but this phase was not executed; the weight of the parking garage would have helped to stabilize the building against the lateral load that is now causing problematic structural movement. Emergency repairs to the building have already been implemented, but the longer-term stability of the building requires a new retaining wall to eliminate the lateral load from the adjacent hillside. He summarized the previous presentation of the concept design, including a landscaping proposal and a new pedestrian bridge and stair tower connecting the building's existing elevator tower to North Road for use by staff.

Mr. Pruitt summarized the Commission's concerns from the February 2011 review of the project. One concern was that the cast-in-place concrete wall would be finished to resemble stone, which would likely result in an unnatural appearance; the Commission had suggested consideration of a finish that is more appropriate to concrete. Another concern was the potentially unattractive repetition of the finish pattern across the substantial length of the wall, and the inevitable intrusion of expansion joints on the pattern. An additional concern was the appearance of the pedestrian barrier at the top of the wall.

Mr. Pruitt said that, subsequent to the February presentation, the design team has met with National Park Service staff to discuss the type of finish that would be appropriate in the context of Rock Creek Park; the design team also inspected existing walls in the park and noted several design features, such as quoins, that could be incorporated into this project. As a result, the design proposal now includes alternatives with quoins that would provide relief to the wall's flat alignment and would help to conceal the expansion joints. He noted the Commission's suggestion of adding buttresses to the wall design; large buttresses would be problematic due to the potential for interference with the future parking garage design, but smaller buttresses would be feasible. He presented the six finish patterns that are now proposed: an ashlar pattern, either continuous or with quoining, all of which respond to the National Park Service's request for a stone-like finish; bush-hammered concrete; a horizontally striated pattern, as used elsewhere in the zoo; and a gridded panel pattern. He also presented several alternatives for the railing design, based on precedents elsewhere in the zoo; he said that the wire mesh fence is preferred by the design team because it tends to become the least visible when foliage has grown around it.

Mr. Pruitt requested the Commission's approval of the overall concept for the wall. He said that the treatment of the wall's base will be studied further, with the possible inclusion of existing rock formations that would give an undulating ground-level profile. The investigation of ground conditions is also resulting in the identification of deeper soil areas where tree clusters can be planted, further concealing some of the wall's elevation.

Ms. Plater-Zyberk commented that the site inspection has raised further issues with the planning for this area of the zoo. She asked why North Road would be widened to three lanes at this location. Mr. Pruitt responded that the master plan for the zoo calls for widening the road along its entire length, and the retaining wall would be aligned to accommodate this future widening while also addressing the near-term structural issues of protecting the General Services Building. Ms. Plater-Zyberk observed that the widening would not accommodate greater speed on the road but would instead accommodate turns; while the turning may be useful in other parts of North Road, this may be an unnecessary feature in this location. She said that eliminating the planned widening could result in a different design for the retaining wall that would reduce its negative impacts. She added that a range of design scenarios could be considered: a minimal solution to address the structural concerns would be to insert a new retaining wall immediately behind the existing wall, ranging to a maximum scenario designed to accommodate the large parking garage that is outlined in some of the elevation drawings. She said that the current proposal is in the middle of this range, accommodating the road widening but not addressing the design of the future garage. She described the result as a confusion of design goals, offering the example of the narrow space that would exist between the proposed retaining wall and the future garage, perhaps too narrow to accommodate the garage's construction.

Ms. Trowbridge noted the Smithsonian's master plan for the zoo, which was approved by the Commission several years ago. Ms. Plater-Zyberk observed that a master plan is prepared at a broader scale, while the smaller-scale design of individual projects can result in the need to reconsider the proposals. Ms. Trowbridge said that the parking garage was included in the master plan, and the transportation component of the master plan was carefully reviewed by the National Capital Planning Commission. She added that the widening of North Road would accommodate turns and might also accommodate some type of alternative transportation system that may be developed. She said that eliminating this potential widening through a different alignment of the proposed retaining wall would require reopening the sound concepts of the master plan. Ms. Plater-Zyberk observed that the current proposal is therefore intended to accommodate the maximum scenario for development of this area, even if the development will be in the distant future; Ms. Trowbridge confirmed this intention. Ms. Plater-Zyberk said that the Commission's review should therefore include the maximum scenario, including the parking garage design.

Mr. Pruitt responded that the outline of the future parking garage, as shown in the submission drawings, is based on the master plan's depiction and has not been designed further as part of the current proposal. He noted that the drawings also include a depiction of the current proposal without the future parking garage. He acknowledged that the master plan had envisioned that the retaining wall and garage would be undertaken simultaneously, but the wall has become a more urgent project. He added that the master plan suggests that a trolley system could use the future third lane of North Road, providing visitors with a more convenient way to move through the zoo's hilly topography. The parking structure would also allow for the elimination of several existing surface parking lots along North Road, and these areas could be converted to green space or exhibit areas. He said that planning for the garage is ongoing, including a design charrette that was held the previous day.

Mr. Luebke suggested that the Commission focus on the proposal's impact on the appearance of the zoo and of the setting for Rock Creek Park. Mr. McKinnell said that the Commission could continue to honor its approval of the master plan; however, this approval included the idea of a parking garage but not the physical form of the intervention at this location. Mr. McKinnell said that the appropriate design for the retaining wall might be much more apparent if it were part of an integrated design submission that includes the road widening and the parking garage; instead, the submission requires the Commission to review a design for the wall without the longer-term context information. He observed that an attractive finish for the wall would be an unnecessary expense if the wall will be concealed by the garage in two or three years; the more appropriate design solution would be to create an attractive garage such as with a stepped profile and extensive planting.

Ms. Plater-Zyberk emphasized the complex problem of the site's appearance from the park, as seen in the Commission's site inspection. The existing condition includes a zone of trees between the park and the General Services Building with its rooftop parking, and then an additional zone of trees along the slope between the building and North Road. The proposed retaining wall would require clearing the trees along the slope, and the remaining trees north of the building toward the park would not screen the new retaining wall; a beautiful wall design would therefore be desirable, and the Commission could offer guidance on achieving this. However, if a multi-story parking garage is constructed in front of the wall, the result will be a massive structure that is very visible from a relatively narrow portion of the park; she noted that such situations exist elsewhere along Rock Creek Park but typically include a generous amount of park space in front of the large structure, which is not available at this location.

Mr. Pruitt summarized the Commission's guidance that the future parking garage should be designed with a soft appearance that is compatible with the nearby landscape. He noted that the recent studies for the parking garage include using the top surface as an event space rather than for parking, possibly designed as a green space that could be used by visitors for picnics; he said that this treatment may be compatible with the Commission's guidance. Ms. Plater-Zyberk agreed, and said that the garage could also be designed to use the retaining wall as one of its sides, rather than creating a narrow pit between the two projects. Mr. Pruitt said that this issue was studied, and the engineers concluded that the void space would be a useful feature to accommodate the periodic need for placing hydraulic jacks that would maintain the retaining wall's tieback system; this equipment access would not be feasible from within the parking levels. He added that the void would also provide additional ventilation and natural light to the garage.

Mr. Rybczynski commented that the Commission role is to be concerned with the appearance of both Rock Creek Park and the zoo, whereas the Smithsonian's concern is limited to the zoo. He observed that the zoo forms part of the major visual setting of the park. However, from the Smithsonian's perspective, the park is at the back of the zoo, and the park edge has therefore been treated historically as the rear yard; he described the resulting relationship of the zoo's edges to the park as "unconscionable" and said that parking, particularly a multi-story parking garage, is not appropriate along the park's edge. He said that this problem became more apparent in the site inspection, and added that the treatment of the garage's roof surface does not significantly affect the conflict. He recommended that the garage be minimized or stepped in profile.

Mr. Rybczynski noted that the garage has been planned but unbuilt for over thirty years and asked if the proposal for the retaining wall would be different if the assumption were dropped that a parking garage will be added later. Mr. Pruitt responded that the issues for the wall would be an economical and speedy solution that can be executed with the currently available funding; a more complex design would lengthen the schedule and might result in the General Services Building becoming unsafe for staff use. He noted that the overall plan for structural repairs is a four-year project, a schedule that allows for the building's necessary functions—including services such as maintenance shops and food preparation—to remain operational.

Mr. Pruitt said that the site of the proposed retaining wall had been cleared of foliage in the 1970s, at the time of the General Services Building's construction. Its previous landscape condition was not documented; reportedly, the hillside had been used for animal grazing. Ms. Plater-Zyberk acknowledged that the current condition is not a designed landscape. Mr. Pruitt added that the project team is aware of the impact on Rock Creek Park's appearance and is coordinating closely with the National Park Service, with the intention of mitigating the problematic adjacency described by Mr. Rybczynski. The current result of this coordination is the effort to relate the proposed retaining wall to the design of other walls in the park, through both pattern and color. He added that the initial study of rock-textured concrete form liners resulted in only very shallow relief; however, further coordination with a design firm has resulted in a potential four-inch depth to the rock pattern, providing greater potential for shadowing and the treatment of joints.

Ms. Plater-Zyberk said that the patterning of the wall could be resolved well but is not the primary issue. She suggested that the Commission evaluate the wall with the assumption that the garage would not be built; Chairman Powell supported this approach, and Ms. Trowbridge acknowledged that the Smithsonian is submitting only the retaining wall proposal. Ms. Plater-Zyberk characterized the proposal as essentially a road-widening project; Ms. Trowbridge added that the proposed concept also includes the stair tower and connection between North Road and the General Services Building. Mr. Luebke noted that the large scope of the retaining wall project may be excessive in isolation, and a more limited solution may be preferable. Mr. McKinnell said that a structural engineer might suggest a different solution if the project scope is simply to protect the General Services Building from further damage. Mr. Pruitt responded that a swale would be provided to channel water away from the building, and the building's wall would be reconstructed. Ms. Plater-Zyberk suggested that the new building wall and retaining wall be designed to accommodate restoration of the sloped hillside, resulting in a reduced visible height for the retaining wall. Mr. Pruitt responded that this issue is already being studied in relation to the existing rock formations along the ground, which will result in an undulating base for the retaining wall; the swale would be adjusted to follow the topography.

Ms. Plater-Zyberk offered a motion to approve the stabilization of the General Services Building and the construction of a new retaining wall that would be aligned to accommodate the expansion of North Road, with the space between the wall and building to be treated with a swale and slope—perhaps extending beyond the rock outcroppings—that would minimize the height of the wall. Mr. McKinnell added that the retaining wall's design could include knee walls for planting as part of a design that steps up the hillside. Chairman Powell said that this motion would support further development of the wall's design for review by the Commission. Mr. Rybczynski described this guidance as encouragement of a design involving substantial berms. Mr. Pruitt reiterated the study of existing rock profiles; Mr. Rybczynski clarified that the issue is the creation of a berm with significant height, not merely the existing rock's height of a couple of feet. Mr. Pruitt responded that recent study has shown that one of the rock outcroppings is approximately ten feet high. Mr. Luebke asked if the Commission is supporting the current concept proposal or asking for a new design. Ms. Plater-Zyberk said that the guidance is for a new design approach; Mr. Luebke suggested that the Commission therefore not approve the submitted concept. He questioned whether the Smithsonian would be willing to pursue a different design concept, noting the repeated emphasis on the urgency of the project.

Mr. Rybczynski suggested that the Commission request the submission of an alternative design. Mr. McKinnell suggested a general approval of protecting the building and replacing the retaining wall, with a request for further design options for treatment of the hillside. Ms. Plater-Zyberk emphasized the Commission's overall support for protecting the building and for accommodating the future widening of North Road, while not supporting the planar concept of the retaining wall which is apparently intended to accommodate the future parking garage that has not yet been designed. She said that this guidance could be expressed as a limited concept approval or as a refusal to approve the submitted concept. Mr. McKinnell and Chairman Powell suggested a limited concept approval; Mr. McKinnell said that the issue requiring further study is the treatment of the wall's face, possibly including a stepped landscape or sloped terrain. He acknowledged that the resulting design might include multiple retaining walls.

Chairman Powell suggested that the Commission request a further design presentation without taking an approval action on the current concept submission. Mr. Luebke said that the subsequent presentation would be another concept submission; Chairman Powell noted that this is a common occurrence, as seen with the previous agenda item. He emphasized the Commission's desire not to delay the protection of the existing building from further damage. Ms. Plater-Zyberk supported this request for a subsequent concept presentation. The discussion concluded without a formal action.

C. American Battle Monuments Commission

CFA 17/MAR/11-3, Cambridge American Cemetery and Memorial, Cambridge England. Interpretive center and restrooms. Revised concept. (Previous: CFA 20/JAN/11-3.) Mr. Simon summarized the Commission's comments from January 2011 in its initial review of the proposed alterations to the Cambridge American Cemetery, with a request for further study of the parking expansion, pedestrian circulation, and the siting of the interpretive center. He asked consulting architect Harry Robinson, the former chairman of the Commission, to begin the presentation.

Mr. Robinson acknowledged the helpfulness of the Commission's comments and the ongoing staff consultations; he said that the new proposal responds to the concerns that have been raised, and noted that the presentation includes some additional changes that are not shown in the submission booklet. He introduced John Cole of Bland Brown & Cole Architects to present the design.

Mr. Cole identified the four key features of the American Cemetery—the memorial wall, the chapel and reflecting pools, the flagpole, and the burial ground—and the intention to make several additions and improvements to the site, which was originally designed by the Olmsted Brothers firm. He said that all of the changes would occur within a 50-meter wide strip along the site's road frontage and would not intrude on a cone of vision from someone standing at the first pool within the cemetery; the portion of the forested area forming a background to this view would be unchanged.

Mr. Cole presented the proposal to increase the capacity of the parking lot by creating five clusters of parking spaces within the tree near the edge of the site, a concept that was described but not well documented in the previous submission. The existing original access road for parking would remain; he said it is in good condition, and any significant alterations may damage the adjacent trees which are now mature. Smaller trees would be removed in some areas; larger trees would remain and parking spaces would be omitted from the clusters where necessary to accommodate them. Additional trees would be planted as indicated on the site plan, with a net gain in the number of trees. A meandering walk would connect the parking clusters and lead to the cemetery's entrance gate. He indicated the bus drop-off area on the other side of the entrance gate, enlarged to accommodate three buses rather than two.

Mr. Cole described the proposed restrooms building that would frame the entrance plaza, replacing the inadequate restroom building that would be razed to accommodate the expanded parking area. The previous submission had shown an open walk passing through the new restroom building as part of the connection between the parking area and the entrance plaza; in response to the Commission's comments, this opening is now eliminated and people arriving from the parking would join those arriving from the bus drop-off area to enter the plaza through a single gate. The plaza is large enough to accommodate a busload of visitors and provides orientation and access to the cemetery's main features. He added that the restroom building would be a mirror image of the existing visitor building.

Mr. Cole presented the revisions to the concept for the interpretive center, to be sited in the wooded area behind the visitor building; the proposed location responds to the view corridors within the cemetery that are to be protected. The interpretive center would have a gable roof similar to those of the visitor building and the proposed restrooms building, and the access road's alignment has been adjusted to provide a view of the sequence of gables formed by the buildings. The interpretive center would be a simple building containing exhibit space, and its exterior would generally not be prominently visible. The building would be raised slightly so that the foundation of its front veranda could be designed to avoid damage to existing trees; a ramp on one side and steps on the other would provide access to the veranda. Portland stone columns at the entrance would be similar to the entrance columns of the existing visitor building; the walls would be purple-red brick laid in a Flemish bond with lime mortar, a design that he said would be appropriately less formal than the stuccoed visitor building. He presented the revised alignment of the walk from the visitor building to the interpretive center, indicating a widened area where visitors would have a view toward the flagpole and burial ground; he emphasized that the circular plaza around the flagpole would not be substantially changed.

Ms. Plater-Zyberk asked how the roof of the new interpretive building would relate to the existing visitor building. Mr. Cole responded that the new building's roof would have the same 29-degree slope, but instead of slate the new building would have a lead roof, which he described as a more robust material that would be appropriate in the interpretive center's setting; Mr. Rybczynski and Mr. Powell agreed with this design choice.

Ms. Plater-Zyberk offered several recommendations to ensure that the proposed changes would be more sympathetic with the site. She suggested that the walk between the visitor building and the interpretive center be curved instead of straight and that the defined viewing area be eliminated; the walk could be aligned with one end on the interpretive center's axis, and visitors following the walk's curve would come across the view toward the flagpole and grounds as a natural part of their progression. Mr. Cole responded that the exact configuration of the design elements in relation to the existing trees would be covered in the next submission due to the unique construction constraints presented by each tree; he said that the exact position of the interpretive center may be adjusted further.

Ms. Plater-Zyberk observed that the existing drop-off road has a beautiful series of curves, and she recommended that the proposed enlargement of the bus drop-off area be slightly curved rather than straight; she acknowledged that the buses themselves are long and straight but said that the buses could approach the curb at an angle, and a curve would make the road more graceful and garden-like. Mr. Cole responded that the bus area is constrained by the available space within the site boundary, noting the very busy public road that is immediately adjacent. Ms. Plater-Zyberk emphasized that her suggestion involved adjusting the alignment of the proposed drop-off road without changing its location; the adjustment would include introducing a curve to the hedge alignment, which Mr. Cole confirmed would be transplanted in this area. Ms. Plater-Zyberk emphasized the importance of this area's appearance when no buses are present, commenting that a beautiful curve would be more appropriate than a bus-like character.

Mr. McKinnell recommended further study of the interpretive center's entrance area so that visitors would not face the veranda railing and the side of the ramp when approaching the building, suggesting instead that the entrance steps be aligned with the main doors. Ms. Plater-Zyberk suggested a berm to eliminate the need for a railing; Mr. Luebke noted that reducing the grade of the ramp could also allow for eliminating the railing. Mr. Cole said that the slope is already shallow and the railing could be deleted.

Upon a motion by Ms. Plater-Zyberk, the Commission approved the revised concept with the recommendations concerning the railing, the bus drop-off road, and the walk. The Commission also delegated the review of the final design to the staff.

D. District of Columbia Office of Public Education Facilities Modernization

CFA 17/MAR/11-4, Dunbar Senior High School, 3rd and N streets, NW. Replacement building. Concept. Mr. Simon introduced architects Sean O'Donnell and Matt Bell of EE&K Architects + Engineers to present the proposal for the replacement of Dunbar Senior High School.

Mr. O'Donnell discussed the history of the school and the historic design features that would be referenced in the new design. Dunbar High School dates to the 19th century and has occupied this site since 1917; the school has been important to Washington's African-American community and has had many notable alumni including current civic leaders. He presented drawings and photographs of the 1917 building, which survived until 1977 and remains an important memory for many of the alumni who are involved in the current project. The 1917 building formed a campus with the adjacent elementary school and technical high school, and provided a model for the design of other high schools in Washington. It fronted on First Street, NW, with its sports fields extending toward the west; overall, it had a powerful relationship to its site and a strong civic presence within the urban grid. He described additional features of the historic building that are influencing the current proposal: the prominent entrance which served as a gathering place, as shown in past yearbook photographs; the building's simple, logical organization; its monumental character combined with the manageable scale of its components in support of the academic mission; its use of natural light and ventilation, achieved with tall ceilings and large windows; the articulation of corners and the use of bay windows and towers; the materials that corresponded to the quality of the architecture; and the organization of the school around a large interior space known as "The Armory," the social heart of the school which derived its name from Dunbar's strong ROTC program which continues to the present. He indicated the central position of the armory in the historic plan and section of the school, noting the stacking of special spaces such as the prominently placed library above the entrance hall and the auditorium stage above the pool He presented a historic photograph of the front of the 1917 building along First Street, indicating the lower-scale context of surrounding residential buildings which largely remains.

Mr. O'Donnell said that the 1917 building was replaced with a large concrete brutalist structure at the west end of the site, necessitating the closure of portions of O and 3rd Streets; the athletic fields were then placed on the site's eastern portion, including the site of the 1917 building. He said that the existing building is not well liked, citing such features as its north-facing entrance which is generally in shadow during the school year.

Mr. O'Donnell said that the current proposal is intended to provide a modern school design that responds to the site's history; he emphasized the goal of designing a school with a civic presence that responds to the immediate urban context. He noted the additional requirement to achieve a LEED environmental rating of silver, adding that the goal is to reach a platinum rating. He described the proposal's features of recreating the idea of an important central space, stacking functions, and creating a strong relationship between the building, the sports fields, and the adjacent recreation center. He said that security is an important concern, and the building is designed for easy visibility of spaces; ease of maintenance is also a priority. He noted that the all sides of the new building would be prominently visible from the neighborhood, with no back facade; a large number of people would see the building from New York Avenue a block to the south. He added that parts of the building such as the gymnasium and theater would often be used by the community outside of school hours.

Mr. Bell described the design in more detail, indicating the proposed building location at the east and south portions of the site. He noted the early decision to place the entrance on the south, which will have more daylight than the current building's entrance and will be generally more convenient for the students arriving by bus and Metro; the entrance would face an underdeveloped neighborhood park that extends south to New York Avenue. He said that the building would serve as a backdrop for the sports fields, a configuration that is seen in other Washington high schools; the proposed site plan is intended to reestablish the axial relationship between the building and the field. He indicated the main entrance leading to a multi-use space with a dining area, monumental stair, and a large mural celebrating the life and poetry of Paul Dunbar; this space would function as the equivalent of the historic armory. He described the organization of the building volumes, with a four-story classroom wing to the west along N Street and the theater and athletic facilities to the north along First Street; a tower containing the media center would be located at the corner of N and First Streets, marking the main entrance and providing a landmark visible from New York Avenue.

Mr. O'Donnell explained that the configuration of the program—a total of approximately 260,000 square feet—would allow the academic area to be closed off after school hours while the other part of the building is available for community use. He said the design would include large windows, high ceilings, and several double-height spaces to increase the amount of natural light and ventilation. He indicated the building's varied heights and multiple roofs, some with photovoltaic panels or green roofs. Mr. Bell said the exterior would have a civic presence with a strong base, middle, and top, and perhaps bay windows and towers to recall the 1917 building; the corner tower would also serve as a lantern to define the main entrance and would relate to the scale of the neighborhood context. He said that further adjustments to the massing and scale of the building elements is ongoing.

Mr. O'Donnell discussed the planned phasing of construction: the new structure would be built on the playing field while the existing building remains in use on the west side of the site; after completion of the new building, the existing building would be razed and the playing field would be reconstructed on the west. This phasing would allow the school to operate on the site throughout the construction process without a need for temporary buildings. He said that construction is scheduled to begin in the fall of 2011 and the building would open in August 2013.

Chairman Powell expressed support for the proposal and noted the thorough design and presentation. Upon a motion by Ms. Plater-Zyberk with second by Mr. McKinnell, the Commission approved the concept submission. Mr. Powell asked about the capacity of the school; Mr. O'Donnell responded that it would accommodate 1,100 students. Ms. Plater-Zyberk noted that the presentation included a description of both the outstanding design issues and the process that is being used to resolve them, facilitating the Commission's support for the proposal.

E. District of Columbia Department of Real Estate Services

CFA 17/MAR/11-5, 4501 Kansas Avenue, NW, E.L. Haynes Public Charter School (former Clark Elementary School). Addition and renovation. Concept. Mr. Lindstrom introduced architects Salo Levinas and Antonio Vintro of Shinberg Levinas to present the proposal for an addition and renovation at the E.L. Haynes Charter School with associated site improvements.

Mr. Vintro said that the E.L. Haynes Charter School is a prominent institution that has grown at various sites and now proposes to add a high school to its existing elementary school building in the Petworth neighborhood; an additional middle school is located on a different site on Georgia Avenue. The existing building, a former public elementary school, dates from 1965; he described its character as "structuralist" with a sort of tough beauty. The elementary school would continue to occupy the lower two floors of the existing building which are easily accessible to the younger students, and the high school would occupy the existing third floor as well the proposed addition. He said that the existing building encompasses approximately 60,000 square feet and indicated the rear wing containing a combined cafeteria and gymnasium; the new high school program would add 400 students and requires a gymnasium and cafeteria for the high school's use. He noted the design goal of maintaining the integrity of the existing building and creating an opposing aesthetic for the high school addition.

Mr. Levinas discussed several design characteristics of the existing building that would influence the addition's design: the three-story height, the horizontal lines of the fenestration, and the recessed first floor. The proposed addition is conceived as a bar that would intersect and play with the existing building.

Mr. Vintro said that the design avoids configuring the high school as an "ivory tower" located entirely on the upper floors; instead, the high school's program is brought downward to the ground floor, providing important access from the high school to the playground. The existing and proposed volumes would be knitted together, providing a connection while also clearly separating them; the two volumes would also serve to define the playground space as an urban "middle ground."

Mr. Levinas presented a diagram of the resulting design, with the addition configured as a bar that is broken in half and bent upward to connect to the existing building's third floor. Mr. Vintro and Mr. Levinas described the overall site plan: the existing building is aligned with the grid streets that partially define the site, while much of the proposed addition would align with the diagonal of Kansas Avenue along one edge of the site. Mr. Levinas indicated the proposed garden to the south of the addition that would reconcile the two geometries and guide people toward the high school's entrance which would be located in the glazed area where the two volumes meet; a glass bridge within this lobby would connect the existing and added classrooms that would be used by the high school.

Mr. Levinas said that the education and design context have evolved in the nearly fifty years since the existing building was constructed, and the addition's materials and classrooms would be very different; he added that the design team has been working closely with the educational staff. The design is intended to achieve a LEED environmental rating of silver or higher, affecting the choice of materials. Mr. Vintro described the concept of a brick base providing a connection to the earth, supplemented by a ceramic material that would be used in the recessed first floor. Areas away from the ground would use a warmer natural material such as wood, particularly in the library design. Insulated panels and glass would also be used; he provided samples of the proposed materials. He noted some similarities of the project to a recent addition at the Sidwell Friends School and presented photos of that building; he indicated Sidwell's amphitheater and said that a similar feature would be provided for the Haynes School.

Mr. Vintro indicated several features of the proposed addition: its horizontality; its predominantly two-story height that is deferential to the existing school's three-story height; and the taller space where the volumes intersect, creating a central focus for the complex and defining the relationship of the volumes. He indicated a proposed learning garden and a berm that would define the amphitheater. He emphasized the urban space that would be developed in the project, with the two building volumes serving as a background.

Mr. Vintro and Mr. Levinas described the plans in more detail. The double-height gymnasium would begin at the basement level, reducing the impact of its volume on the overall appearance of the building; it would have an additional separate entrance and could be made available for after-hours use by community residents, who would also have access to the garden and amphitheater. The high school's classrooms would be on the second and partial third floor of the addition as well as the existing building's third floor. The second-floor library would overlook the amphitheater and would have the character of a porch. An outdoor terrace and green roof would be located above the second floor.

Ms. Plater-Zyberk asked about the entrance location for the elementary school; Mr. Vintro and Mr. Levinas responded that it would remain at its existing location near the center of the front facade, on axis with the existing cafeteria wing. Ms. Plater-Zyberk observed that this entrance is directly adjacent to parking spaces as shown on the site plan; Mr. Vintro described it as a drop-off area for the elementary school. Ms. Plater-Zyberk asked how the high school students would arrive. Mr. Vintro responded that most would be walking into the site from the street edges; the parking lot would be used primarily for staff parking and for drop-off of the elementary school students. Mr. Levinas acknowledged the difficulty of determining the best orientation of the entrance; the proposed solution is that students could walk into the site from both the east and west sides, proceeding to the garden which would lead to the high school's entrance. She observed that the new drop-off area shown on the site plan is clearly more convenient for the high school students; she suggested that the redesign of the parking lot include a drop-off location that is conveniently located for the elementary school students as well, and generally to improve the character of the parking area.

Ms. Plater-Zyberk said her larger impression of the project is that the design team has expended a great deal of effort on the new high school addition but the result is not sympathetic to the existing elementary school building. She observed that certain features work well, including the internal planning of the addition and the entrance in the connecting link between the old and new portions; but the addition looks disconnected from the existing building—almost as if the addition were trying to make the older building look bad. Mr. Levinas said that the approach routes to the building entrances may not have been presented adequately, adding that an adjustment to the drop-off area might result in the loss of four parking spaces but could be studied. Ms. Plater-Zyberk clarified that her concern extends to the overall image of the project, not only the entrances. She emphasized that the addition would be unsympathetic to the existing building, adding that the presentation does not even illustrate the appearance of the project from the streets on the north, where one would see both of the building volumes as well as the existing school's cafeteria wing.

Mr. Rybczynski described the concept as a new "hill" that overlaps the existing building but said that the angled form of the addition is not justified; he observed that the junction of the volumes contains merely a hallway, rather than an important space such as the library. Mr. Levinas responded that this junction is the atrium which would includes the entrance door that is the focus of the exterior walk; he described the space as a neck between the two building volumes. Mr. McKinnell noted that the atrium entrance is only for the high school students and asked if the elementary school students would have any reason to be in this space; Mr. Vintro responded that they would occasionally walk through the atrium to reach the new shared-use cafeteria.

Mr. Rybczynski supported Ms. Plater-Zyberk's criticism that the new and existing forms are unsympathetic, he said that the proposed addition's overhanging configuration gives the sense of threatening the existing building. Mr. McKinnell agreed, commenting that the relationship between the volumes is of the new dominating the old; he questioned why the buildings need to be joined at all. He said that the proposal has positive features such as the entrance garden and the berming toward the library, but the overhanging relationship and the junction between the volumes could be avoided if the volumes were entirely separate. Mr. Vintro responded that a separate building was considered but rejected; a connection is necessary because the high school would occupy a portion of the existing building as well as the proposed addition. The bent and overhanging configuration of the addition is intended to convey on the exterior that the high school's classrooms occupy the addition's second floor and the existing building's third floor. Mr. McKinnell acknowledged that this programmatic configuration justifies a connection between the buildings but questioned the proposed form; Mr. Levinas responded that the proposal is intended to be more interesting than merely placing a new volume near the existing volume and joining them with a glass element; the proposed relationship is a volume that begins at the ground and rises to embrace or hide the existing building. Mr. McKinnell acknowledged that the resulting proposal is more interesting but emphasized that it is unsympathetic to the existing building, which he described as "quite handsome."

Ms. Plater-Zyberk said that the issue involves the principles of how to add to existing buildings, and especially to those existing buildings that may not be terribly distinguished. She observed that cities are routinely composed of adjoining buildings dating from different eras and designed in different styles but unified by the street wall; this accumulation of varied buildings constitutes urbanism. She commented that the proposed addition would be a beautiful building by itself, acknowledging the great effort to develop its form, but observed that its effect is to devalue the existing building which is not being redesigned in this project. The result is that the existing building would appear old and outdated while the addition would clearly convey a sense of being newer, more interesting in form, and having better materials. In contrast, she observed that urbanism is typically successful in allowing old and new buildings to exist harmoniously without devaluing one or the other. She defined the design challenge in this project as creating an addition while having some deference to the existing building and not devaluing it. She concluded that the addition should not be approved in the proposed form.

Mr. Levinas said he agreed with Ms. Plater-Zyberk's concerns about the relationship between the two volumes; he clarified that the existing building would be renovated, but the design team decided not to propose recladding or greatly altering it. The proposal is instead to leave the existing architecture exposed and to use its best features, such as the recessed first floor, in the design of the addition. Ms. Plater-Zyberk acknowledged this approach, as already described in the presentation, but said that the result does not fulfill the intentions and instead would create too much of a contrast that would diminish the value of the existing building. Mr. Levinas asked if the problem is the connection between the volumes; Ms. Plater-Zyberk said that the problem is with the overall ensemble. She noted that the contrast would likely be acceptable if the context involved three or four buildings in a row, but with only two volumes the contrast is problematic and disrespectful of the existing building. She said that creating an addition to a single building requires a more direct relationship than the proposal offers.

Mr. Levinas noted that the Sidwell Friends School project involved recladding the existing building with the material of the new addition; he asked if the Commission would recommend this approach for the Haynes School project. Ms. Plater-Zyberk said this might be feasible depending on the details, requiring careful consideration of many issues such as the existing building's proportions and its gridded surface expression.

Mr. McKinnell offered the simpler observation that the proposal appears to be a gymnasium added to a classroom building. He observed that the existing school clearly contains classrooms, as conveyed by its form and materials, while the addition would be an entirely different architectural language. He emphasized the recommendation for more respect and sympathy for the existing building. Ms. Plater-Zyberk acknowledged that altering the character of the existing building could also be a viable design solution; she emphasized that this treatment would not be due to any inherent problem with the existing building's style as part of the broad stylistic mix of the urban fabric, but instead due to the difficulty of designing an addition to an isolated building while avoiding excessive stylistic contrast.

Chairman Powell suggested that the Commission's guidance be summarized in the letter to the applicant, with a request for further study of the concept. The discussion concluded without a formal action.

F. District of Columbia Commission on the Arts and Humanities

CFA 17/MAR/11-6, New York Avenue Bridge over rail tracks. Public art installation on bridge. Concept. Ms. Fanning introduced the proposal for a public art project by sculptor Kent Bloomer, planned for the bridge that carries New York Avenue over the railroad tracks north of Union Station. She said that the project is a collaboration between the D.C. Commission on the Arts and Humanities and the D.C. Department of Transportation; the proposal is for two open-work metal sculptural trees rising from the bridge abutments forming an offset open arch over the avenue. She asked Deirdre Ehlen of the D.C. Commission on the Arts and Humanities to begin the presentation.

Ms. Ehlen said the project results from her agency's 2008 master plan for public art in Washington, which called for improved public art and the selection of better locations; the New York Avenue bridge site emerged from this master plan, and the project is now being undertaken in conjunction with the overall reconstruction of the bridge. She introduced sculptor Kent Bloomer, a professor of architecture at Yale, to present his proposal.

Mr. Bloomer presented photographs of several of his completed projects, including lightposts for Central Park and a window installation at Reagan National Airport. He said that, as an architect as well as a sculptor, he is always concerned with the context of his artwork. He described the form of the New York Avenue bridge: a long flat span above the railroad tracks, supported by columns; and a sloped approach on the west supported by a berm. The sculpture would be located at the transition between the span and the western approach, where the view opens southward to the U.S. Capitol and southwest to a panorama of central Washington. He said the project is conceived as a gateway arch into the NoMa neighborhood that is developing to the west near New York Avenue; it would also serve as a gateway for those departing the central city.

Mr. Bloomer said that his initial studies to encompass more of the bridge seemed excessive; the current proposal is more limited and responds more fully to the engineering constraints. He noted the careful attention to the sculpture's night appearance, with limited lighting that would illuminate the artwork but respect the local concern with maintaining a dark sky. Mr. Luebke asked for clarification of the lighting location; Mr. Bloomer responded that many of the light fixtures would be placed within the sculptural foliage rather than relying on extensive general lighting from below, contrasting this concept to the general lighting of Union Station nearby.

Mr. Bloomer described the overall form of the sculpture as a pair of foliated half-arches. He indicated the stabilizing elements that would allow the artwork to meet the requirement of withstanding high winds, adding that the proposed location at the edge of the berm results from the infeasibility of attaching the sculpture to the bridge's main span. He clarified that the offset alignment of the two half-arches results from the sharp angle of the abutment below that is used for support, resulting from the angle of the railroad tracks.

Ms. Plater-Zyberk asked about the proposed materials; Mr. Bloomer responded they have not yet been selected. He clarified that the lighter-colored elements are solid, not themselves lighting fixtures; he added that the lighting could be eliminated if it is problematic. He said that the two pieces of sculpture would be mirror images of each other, and details of the orientation are determined by the necessary support configuration for the wind bracing. He emphasized that the two half-arches would appear to frame the view as drivers approach from the east, and then their offset would become apparent as drivers get close to the artwork.

Ms. Plater-Zyberk asked if one of the half-arches could be shifted so that the two portions of the sculpture would align, while not necessarily preferring such a modification. Mr. Bloomer said that this change would be difficult and expensive because of the intention to use the bridge's abutment for support; however, a modified support system could perhaps be provided as part of the overall bridge reconstruction project. Ali Shakeri from the D.C. Department of Transportation said that the sculpture's proposed location would identify the edge of the bridge span, which has a significantly skewed alignment; however, he confirmed that the approach segment has its own abutments that could be used to support an aligned configuration of the two half-arch sculptures. Ms. Plater-Zyberk then clarified that the question is whether the artistic preference is to have the half-arches offset or aligned; Mr. Bloomer responded that this is a difficult question which he would consider further, noting that earlier studies had the half-arches on the diagonal to form a continuous span but this version was rejected due to the excessive diagonal length. Mr. Shakeri offered to give further study to the engineering implications of aligning the half-arches. Mr. Powell said that an aligned configuration would make more sense to people experiencing the sculpture, particularly at close proximity. Ms. Plater-Zyberk noted that the offset as proposed may be preferable; one advantage may be to draw attention to views on the left and right at different moments, rather than simultaneously, as people move along the bridge. Mr. Bloomer responded that the purpose of the offset was based on the structural constraints rather than such an artistic intent, and the response from Mr. Shakeri provides new information that could be considered.

Mr. McKinnell complimented Mr. Bloomer on the beautiful project and asked for clarification of which side would be seen when entering or leaving the city. Mr. Bloomer responded that the structural sides would be visible when entering the city—while driving west—and the more three-dimensional foliated sides would be visible when leaving the city, driving east. He said the reason for this orientation is the necessary direction of the wind bracing, which would tie into the berm abutments on the west rather than the less strong cantilevered edge of the clear span above the tracks on the east. He added that this constraint may not be a concern if one of the half-arches is moved further west to create an aligned configuration.

Mr. McKinnell offered support for the offset configuration as proposed. Chairman Powell suggested that the Commission approve the concept and let the artist give further consideration to the choice of an offset or aligned configuration. Ms. Plater-Zyberk agreed, saying that she was not offering a preference for either configuration and would support the artist making this choice. Mr. Bloomer said that he would use the large-scale model in his studio to explore this issue further in cooperation with the D.C. government officials. Upon a motion by Mr. Powell, the Commission approved the concept with the understanding that Mr. Bloomer would further study the relative position of the two sculptural components.

G. D.C. Department of Consumer and Regulatory Affairs—Shipstead-Luce Act

SL 11-065, Office Building, 500 North Capitol Street, NW. Additions and facade alterations. Revised concept. (Previous: SL 11-049, February 2011.) Ms. Batcheler introduced architect Jeff Barber of Gensler to present a set of alternative designs for 500 North Capitol Street, NW, in response to the Commission's previous comments.

Mr. Barber acknowledged the assistance of the staff in developing the alternatives and summarized the Commission's concerns from February 2011: the importance of long views of the site within its broader context of the open space leading to Union Station and the importance of maintaining continuity in the line of buildings along North Capitol Street. He described the resulting recommendation for a simpler, more uniform treatment of the main east facade with fewer varieties of curtainwall, and eliminating the articulation of an end pavilion, so that the east facade would clearly be understood as a single building; the south facade on E Street, having less urban significance, could be treated differently.

Mr. Barber presented the four alternative designs, emphasizing the views of the east facade which had most concerned the Commission. Option 1 has a long facade with little variation; he said this design is most directly responsive to the Commission's comments, presenting a uniform North Capitol Street facade expressed as a continuous glass layer in front of the columns. The east facade would have no articulation of an end pavilion; a metal border would surround the western end bays on the south elevation. Option 2A has a uniform glass facade with a single vertical recess extending from the second to the eighth floor, revealing a second layer beneath the outer curtainwall; a narrow band of the outer curtainwall would continue across the recess at the second and eighth floors. A similar recess would be included on the south elevation. Option 2B is a variation of Option 2A with a vertical slot that would be continuous from bottom to top, without any band of the outer curtainwall extending across the slot. He said that both options 2A and 2B would have a consistent treatment at the ground floor and the top floor. Option 3 would extend the curtainwall down to the ground at one end of each street elevation, creating "bookends" that would bracket the corner and the main entrance; the remainder of each street elevation would be in a single plane.

Mr. Barber said that many features are the same in all four options, such as the treatment of the southeast corner, the use of the curtainwall up to the top of the eighth floor, and the setback of the ninth floor. He added that the design team prefers Option 2B but considers any of the options to be satisfactory and viable for construction. He concluded with a summary of the previous designs that were presented to the Commission, and provided material samples of clear, slightly reflective, and fritted glass for the Commission's inspection.

Mr. Rybczynski expressed appreciation for the design team's response to the Commission's recommendations in all four alternatives. He offered a preference for Option 1 for the east facade because it is the simplest, but supported using one of the Option 2 treatments for the south facade; he added that he could also support Option 2B for the east facade. Mr. McKinnell agreed to support Option 1 for the east facade and either 2A or 2B for the south facade. Mr. Powell acknowledged the simplicity of Option 1 but commented that it appears "relentlessly horizontal" on the east facade; he supported Option 2B on both street facades. Mr. McKinnell agreed to support this recommendation. Upon a motion by Mr. McKinnell and second by Ms. Plater-Zyberk, the Commission approved the concept of Option 2B. Mr. Luebke added that the final design proposal for this project could be placed on the Shipstead-Luce appendix if the staff considers the future submission to be satisfactory; Chairman Powell supported this procedure.

There being no further business, the meeting was adjourned at 3:20 p.m.


Thomas E. Luebke, FAIA