Mira Condominium Tower San Francisco, CA

Safe, efficient, forward-thinking design

The Mira Condominium Tower is a 39-story residential skyscraper located at Folsom and Spears Streets in San Francisco, California. Developed by Tishman Speyer and designed by Studio Gang Architects, the project, at 422 ft. in height, contains 391 condominium units, with 156 units (approximately 40 percent) designated below market rate.

The building offers a unique visual profile and design aesthetic to the heart of the city. Twisting incrementally over the height of the tower, its bays, modeled after the classic bay window typical of early homes in San Francisco, make every residence a corner unit and provide ample views, natural light, and fresh air.

The Goal: Efficiency, Sustainability, & Safety

Efficiency and sustainability were key considerations in the design and construction of the Mira Condominium Tower, as the team sought to achieve the ambitious California Title 24 energy standards. Additionally, great thought and careful selection was given to the building’s sustainable features and materials, as Mira Condominium Tower was built to target LEED Gold certification. Given its height and use as a multiunit residential building, fire safety was also a top priority.

The Challenge

Due to its complex design and twisting bays, the building would require a sophisticated curtain wall façade. Careful attention would be required during install of the continuous exterior insulation, with particular consideration paid to gaps, penetrations, seams and other detailing. Because the incomplete exterior of the building would be exposed to the elements for some time during install, it was imperative to select an insulation material that could withstand exposure to moisture and the elements.

The Solution The building’s distinctive form and texture can, in part, be attributed to the building’s energy performance and how it is experienced. The bays allow for a high-performance façade that features a curtain wall system incorporating ROCKWOOL stone wool insulation. A continuous layer of ROCKWOOL Comfortboard® 80 envelops the building to create an exceptionally efficient envelope that offers a high level of occupant comfort. Comfortboard® 80 was the product of choice for this project, as contractors preferred its quality, density, rigidity, durability and handleability. Opting for Comfortboard® 80 reduced install time and saved on costs, as it allowed the insulation to be installed in keeping with the Mira Condominium‘s Construction schedule, whereas an alternative like spray foam would require installation during off-hours and require time to dry.

With sustainable, energy-conscious features, such as ROCKWOOL Comfortboard® 80 continuous exterior insulation, a state-of-the-art graywater harvesting system, green roofs, and high-energy fixtures to name a few, Mira Condominium Tower is on target for LEED Gold certification. In terms of efficiency, the building actually surpassed its objective and now exceeds the strict energy standards set out by California Title 24.

Residents will not only feel good living in a beautifully well-designed, comfortable, and environmentally conscious building, they will also benefit from the care given in the selection of fire-safe materials. As a substantial residential tower— the building required special upzoning to accommodate its height—occupant safety was key consideration. This was the primary reason noncombustible stone wool, and in particular ROCKWOOL Roxul Safe™, was chosen as the fire-safing insulation. The material can withstand temperatures up to 2,150˚F, can help limit flame spread in the event of a fire, and does not contribute to harmful smoke or toxic gases.

ROCKWOOL was also selected due to its high quality composition, multiple benefits, ease of install, sustainability profile, as well as the company’s top notch customer service and technical expertise.