This article, published in Studies in Conservation (63, sup 1, 242-250) was presented at the 2018 IIC Congress in Turin. I remember being in the auditorium and was captivated by the efforts the Museum made to ensure a more sustainable future for the expanded building. When researching and gathering stories for this special NiC issue, Jill and Roberta’s paper was one of the first that sprang to mind. Here I present excerpts from the paper. You can read the full article in SiC HERE, available for free with your IIC membership. (Sharra Grow, News in Conservation, Editor in Chief)
The shorter version is also in the latest edition of News in Conservation.
By Jill Sterrett and Roberta Piantavigna
In 2016, the San Francisco Museum of Modern Art (SFMOMA) opened a very large-scale expansion that has significantly impacted the museum’s educational, social and economic role in the city. Since its foundation in 1935, SFMOMA has been a museum of and for its times, with an early embrace of modern media such as photography, regular evening hours for a working public, and traveling exhibitions that reached remote regions of rural California.
Before the project was announced in 2009, it was necessary to ask, why expand? How would an expansion enhance the core purpose of bringing individual visitors face-to-face with art in such a way that each is richer for the encounter? SFMOMA is on pace to triple the number of schoolchildren served. The galleries have more than doubled, from 4600 to 12200 m2. The museum is free, in perpetuity, for everyone under 18 years of age. Free art-filled spaces in the museum increased from 1600 to 4200 m2. These are but a few of the community-minded ambitions that guided this expansion.
Situated in the Bay Area, a center for environmentally progressive thought and energy regulations, the expanded SFMOMA had to comply with the rigorous building standards of San Francisco’s Green Building Code. Adopted in 2008, these requirements apply to newly constructed residential and commercial buildings and major renovations of existing buildings.
FORM THE DESIGN TEAM
Working with the cross-disciplinary museum team, SFMOMA’s architecture firm Snøhetta managed the design process and engaged sustainability consultants Atelier Ten and local architecture firm Esherick, Homsey, Dodge, and Davis (EHDD) to spearhead LEED coordination. The engineering firm Taylor Engineering and commercial lighting design consultants Arup identified two critical areas of collaborative exploration and study for the relatively mild climate of the San Francisco Bay Area: environmental conditioning guidelines for the museum and LED (light emitting diodes) lighting options for the galleries, study rooms and storage vaults.
DEVELOP AND SOCIALIZE THE PROPOSAL
SFMOMA considered HVAC controls to be an essential feature of the expansion for two reasons. First, for 60 years from 1935 to 1995, SFMOMA operated in a civic building without relative humidity (RH) controls. Staff at all levels had experienced the untoward effects of fluctuating temperature and RH on the collection. Second, to operate in 2018 without climate control sanctioned by the museum sector would put the traveling exhibitions program in jeopardy. With this in mind, the design team reviewed the conservation literature on museum climates. Next, conservation staff consulted with the Bizot Group and conducted a survey of colleagues who had completed museum construction projects within the last five years.
SFMOMA engaged in three stages of peer review to assess the building design team’s recommendations. In 2012, the museum hosted a one-day Sustainability Roundtable. Following that meeting, the proposed guideline was presented for peer review at the Climate Control Standards: Fact or Fallacy roundtable held at the 2012 American Institute for Conservation (AIC) Annual Meeting where the ASHRAE Class A category was approved as the basis for a new museum climate guideline. Finally, this ASHRAE Class A category was ratified as an acceptable solution by the American Association of Museum Directors (AAMD) in 2013.
HEATING, VENTILATION, AND AIR-CONDITIONING
Taylor Engineering’s innovative system played an important role in achieving many LEED system credits. First, the centralized adiabatic system reduces significantly the energy consumption compared to previous zone-controlled steam humidification methods. Furthermore, additional engineering features that enhance the building’s energy performance include: using optimized fan wall arrays that turn fans on and off based on the static demands, shutting down air during unoccupied hours while monitoring the desired temperature and humidity parameters and starting back up if needed; redeploying existing equipment when possible; and adopting new, water-efficient fixtures.
A 230 m2 cool and cold storage vault for color photography exists within the museum envelope. It is a two-zone vault that preserves the photographs in the collection while also providing the ready access upon which artists, curators, scholars, and students rely. While the preservation benefits of an even colder vault are fully acknowledged, colder conditions are neither cost effective nor energy efficient for a collection in such high use as SFMOMA’s. Human processes for accessing the collection have been designed to keep energy draw to a minimum. To accomplish this SFMOMA staff has developed a plan for the cold vault whereby the storage space is accessed only three days per week. This plan minimizes fluctuations in temperature and therefore extends the usable life of the photography collection while also limiting unnecessary energy draw.
MUSEUM ILLUMINATION AND SOLID-STATE LIGHTING
SFMOMA worked with Snøhetta and Arup to construct a complete full-scale gallery mock-up, including floors, walls, ceiling details, and all of the short-listed LED lighting options under consideration. Select works from the SFMOMA collection were installed within this mock gallery for viewing to build broad interdepartmental consensus around the LED lighting option that provided the optimal balance between aesthetic qualities of viewing, long-term preservation of artworks, and overall energy efficient design.
The LED fixture selected for use throughout the building is LSI Lumelex 2044. The color temperature is 3000 K with a color rendering index over 90 which delivers a quality of light, color temperature, stability, and ease of use. In photography galleries, fixtures were customized at the track head to be able to adjust the output from 100% down to 10%. This provides great control and flexibility when multiple light levels are called for in the same gallery, even on the same wall. The new LSI fixtures include a variety of reflectors and lenses to shape and manipulate the beam spread.
Natural light floods the office floors as both an energy-efficient and highly agreeable light source. San Francisco’s Mediterranean daylight selectively augments gallery lighting throughout the building. In the Botta atrium, inspired by a lively populated Italian piazza, the light funnels from the top of the turret, through its enormous circular skylight. A set of LED fixtures are placed ad hoc on the roof to guarantee even illumination to large works that are usually installed on the walls by the main staircase or suspended above the entrance. The fourth and fifth floors have the capacity for daylighting through a series of diagonal skylights. In the new building, gallery windows and skylights are equipped with block-out and solar shades to moderate the light intensity on the artworks. These shades are computer controlled based on time of day or light detected.
ADDITIONAL ENERGY-SAVING MEASURES
A living wall, the largest public vertical garden of its kind in the country, was designed as a subtly monochromatic green mosaic made of 19,442 plants from 38 different species, including 21 native plant species found in East Bay Regional Parks and nearby Mount Tamalpais. These native plants used on the living wall and on other areas of the project are locally sourced and help keep water use low. Water savings are manifest in other ways as well. Stormwater is reused for toilet flushing, and low-flow fixtures are specified throughout. Stormwater is used for irrigation of the living wall and is also re-circulated within the wall system. These systems all contribute to the 60% decrease in potable water use in the new building for visitors and staff.
Fire-resistant glass fibre-reinforced polyester resin composite with a polymer concrete face coat was used in the US for the first time as exterior cladding on SFMOMA. The new exterior façade is not just lightweight and sculptural, it is also a highly sophisticated energy efficient building envelope that helps minimize energy use. The fiber-reinforced polymer panels were cast using an expanded polystyrene foam mold, which is not only an economical and recyclable material, but also served as the perfect handling cradle for the protection and safe installation of each panel. The reduced weight required less structural steel than a façade made of heavier materials such as stone, concrete, or masonry.
COMMISSIONING, STAFF TRAINING & EVALUATION
In winter 2015, the City of San Francisco granted the temporary certificates of occupancy to the museum to allow staff to move into the building and to launch the six-month art installation plan for the roughly 1500 artworks on display on six gallery floors for the official opening in May 2016. Art was installed only after two critical conditions were met: the climate was recorded at the established parameters of temperature and RH and the security system was fully activated. New staff and security guards were also trained to oversee the artworks during installation.
Although frenetic, these challenging months were an invaluable bonding experience for the teams who continue to collaborate to operate the museum.
Building engineers have had to work closely with Taylor Engineering to understand the mechanical infrastructure. They have also worked closely with the programmers who developed the software to monitor internal climate readings. In turn, SFMOMA building engineers have been teachers to a range of museum staff, primarily conservators, to ensure that their knowledge of building conditions is disseminated to collections stewards across the museum.
SFMOMA’s compliance with San Francisco’s Green Building Code was confirmed in summer 2017. In the first operational year of the expanded SFMOMA, there was a 34% reduction in electricity and 44% reduction in gas used per unit area, as compared with the museum in 2012–2013 when the building had a 50% lower footprint. Likewise, the overall energy use intensity of the building is 37% less. Despite having a larger, more intense program with new cold vaults for color photography, the museum uses significantly less energy per unit area.
Existing methods for evaluating energy efficiency within the fields of architecture and engineering have led the museum to seek corollary means of conducting an evaluation of the building as an edifice for cultural collections. Enlisting expert sustainability evaluators to customize an assessment action plan that will serve as a model for the cultural heritage sector is the work that is presently underway at the new SFMOMA.