September 27, 2019

Low-rise structures

Photo provided by WACA

Cast-in-place concrete walls enclose the auditorium, providing structure as well as isolation, acoustical reflection and finish.

Vashon Center for the Arts

Location: Vashon

The design of the Vashon Center for the Arts focused on embracing the island’s rural setting. A classic barn design structure, use of rustic materials, and mix of concrete elements reflect its Pacific Northwest character.

Modern design touches greet visitors with a north-facing glass wall mixed with high-gloss, polished concrete flooring in the reception area, offering a flood of daylight to interior spaces and a welcoming night beacon for evening performances.

Cast-in-place concrete walls enclose the auditorium, providing structure but also isolation, acoustical reflection and finish. The concrete walls support a 60-foot span, utilizing a heavy timber aesthetic. Roof weight and long spans were addressed by setting trusses with slotted holes to allow for sliding, housed within the concrete walls. The walls were finished with a matte-black concrete stain to reduce reflections in the performance space. The result is responsive to architectural aesthetics and developed with the integration of concrete, wood and steel.

Acoustical considerations included two distinct criteria for the structure’s development: shield outside noise and provide responsive theater acoustics to performance type. Situated on the island’s main road, outside transient sound includes sirens, traffic and jet noise. Exterior noise solutions included the use of concrete walls for mass that also served as shear wall.

Inside the theater, the acousticians wanted to create a degree of surface roughness on the side walls to scatter high frequency sound and reduce its strength. The concrete walls were built utilizing forms liners to create deep, vertical lines and wide surface variations to provide micro-reflections when sound approached the walls from oblique angles. Wood slats were added to the vertical grooves in the concrete walls to further enhance high-frequency diffusion while supporting the natural aesthetic. The thoughtful integration of concrete and wood provides high-quality acoustics for single performers to large musical productions. Stepped seating areas over a full air plenum below the seats completes the concrete auditorium floor system, which also encloses the orchestra pit. The design provided the ability to step the concrete floor while maintaining the curvature and steps for seating rows.

Because of the cost of ferrying construction materials to Vashon, sourcing concrete with a local concrete supplier proved to be the most cost-effective solution for the owner. Owner advocacy throughout the project was a primary focus for the team.

Other Stories:

• GRAND AWARD
  Infrastructure (transportation)
  
• Low-rise structures (tilt up)
  
• Mid-rise structures (nonresidential)
  
• High-rise structures
  
• Infrastructure (non-transportation)
  
• Concrete paving
  
• Architectural and artistic
  
• Sustainable and resilient