OG 23-163

OG 22-163 (HPA 22-264)
1703 32nd Street, NW (Square 2155, Lot 812)
Construction of new three-story public program building
Design Development

REPORT: In 2021, OGB recommended concept approval for a proposal at Dumbarton Oaks to convert the existing 1925 McKim, Mead, & White greenhouse—adjacent to the relatively new library—into a classroom, studio, and gallery space, and to construct a new greenhouse near the northwest corner of the property. Since then, the applicant has transposed these two uses, now renovating the historic greenhouse for its original use and constructing the proposed new public programming building in the other location. Plans to renovate the historic greenhouse were approved by the Commission in June 2022; a new concept to construct a new three-level public programming building and associated site work was approved by the Commission in June 2022.

In its concept review in April 2022, the OGB commended the institution for rethinking the planning of the original proposal, noting that the new disposition of uses is more successful by retaining the greenhouse’s original use, activating the western part of the campus, and constructing a building that is more engaging than the previously proposed new greenhouse. The OGB supported the proposal to reconfigure the existing service court and associated mechanical equipment, creating a new public presence at the western end of the Dumbarton Oaks property and activating access to the public parkland to the north. The new building— rational in plan and compatible with the scale of historic structures on the property—is simply articulated as a brick pavilion with a more open, glassy second floor, allowing the focus to remain on the beauty of the historic property. A lower level with studios and gallery space opening to an outdoor terrace also encourages engagement with the grounds. The OGB found the scale and massing of the proposed building to be harmonious with the landscape and adjacent buildings, and the materiality of the design blends well with the surroundings. For the development of the design, the OGB requested further presentation of the masonry bases and suggested refinement of the spacing and dimensions of the window openings, possibly to create more solidity at the outer corners and more vertical proportions.

In its design development-phase review of a revised concept design this month, the OGB expressed continued support for the proposal, noting that the restrained design is complemented by the intelligent floor plans. The OGB found that the revised submission addresses previous comments and clarifies questions about materiality with the inclusion of sample images. The Board acknowledged the need for the addition of the new exterior stair, which is a change from the concept proposal, but suggested that it be designed to relate to the roof by using zinc- colored materials. The OGB expressed a strong preference to consider operable wood windows with exterior blinds as proposed in the 2022 concept drawings.

RECOMMENDATION: NO OBJECTION to revised concept design for new three-level public-program building, per materials received 17 April 2023, PROVIDED the applicant strongly consider the use of wood windows as proposed in the concept design and zinc-colored materials on the exterior egress stair to match the roof. File permit submission at DOB with details and dimensions drawings for review by the Commission.