Looking almost parasitic in nature, an amorphous, ballooning silver volume stretches out to envelop a more traditional building in new renderings of Steven Holl Architects’ “Encased.” Chosen as the winner of an international competition to design a new concert hall in Ostrava, Czech Republic, the design adds to the existing House of Culture, itself an austere travertine-clad complex completed in 1961.

The new 1,300-seat concert hall is described by the architects as “a perfect acoustic instrument in its case,” hence the name. It’ll soon house the Janáček Philharmonic Orchestra, too — the nation’s leading orchestra for commissioning contemporary music.

The metallic, vaguely alien nature of the exterior is softened by an interior lined with warm maple wood. Built on both sides of the House of Culture’s wings, the structure features dramatic cantilevered elements with a wide base at the rear and a slender, neck-like volume in the front. If you’re prone to seeing the shapes of living creatures in architecture, you might imagine the addition as either embracing or biting down upon the existing building, depending on how you look at it.

“The smooth case of zinc holds an ‘instrument’ in an extended vineyard-type plan made of concrete and maple wood,” explain the architects. “Czech composer Leoš Janáček’s theories of time will guide and give order to the concert hall’s interior geometry. Acoustic wall panels are organized according to scasovani, or rhythm, in three variants: znici = sounding, scitaci = counting, and scelovac = summing.”

They add that the hall faces the existing park at the rear of the building in order to soften urban traffic noise, while a new entrance on the promenade “rises to glide over the top of the existing historical Cultural Center in a sky-lit lobby for the new hall… a dramatic complimentary contrast between new and old creates a cultural landmark for Ostrava.”

Of the winning design, jurist Rafi Segal says, “It’s not the size of the building, but the importance and significance of it.” Another jury member, Krzysztof Ingarden, says “it is a fantastic piece of architecture [that considers] very well the relationship between the City of Ostrava and the park behind the existing building. I believe the winning project will be an emblematic piece of architecture for Ostrava [and revitalize] the city as well.”

Steven Holl Architects is known for taking risks with unconventional architectural shapes and forms like Maggie’s Centre Barts in London, monolithic metal-clad desert homes, and the delightful organic modernist “Ex of In” House. Most of the time, those risks pay off in spectacular fashion, with finished projects feeling fresh and unexpected.

Sometimes, their radical vision for architecture unconstricted by rectilinear norms hits predictable engineering snags, however, like their so-called Copenhagen Gate: the bike lane in the sky that might have been but got canceled due to safety concerns.

Construction hasn’t yet begun on this project, but it’s unlikely the new Ostrava Concert Hall will be plagued with similar problems. It’s set to open in 2023 and will be produced in collaboration with the Czech firm Architecture Arts.