SMUD Museum of Science and Curiosity Wins Metal Roofing Award
December 1, 2021
From the December 2021 issue of
Metal Construction News.
By Christopher Brinkerhoff
Precise design, fabrication and installation make zinc dome a showstopper
Driving on Interstate 5 along the Sacramento River north of downtown Sacramento in California, travelers see an unusual looking building with angled stripes on its walls and topped with a giant, glossy silver-gray dome. It is no coincidence the gray dome looks like a planet emerging over a horizon, and the angled, dark stripes, called vectors, allude to space and mathematics. Inside the dome, there is a planetarium. And inside the building, visitors to the SMUD Museum of Science and Curiosity (formerly the Powerhouse Science Center) learn about science, technology, engineering, arts and mathematics (STEAM).
The judging panel for the 2021 Metal Construction News Project Excellence Awards noted the zinc cladding on the dome was expertly and precisely designed and built. The zinc dome is a beautiful object constructed with highly skilled craftsmanship, the panel agreed, and they gave the project the award in the metal roofing retrofit category.
Chris Holt, AIA, LEED BD+C, associate, project manager at Dreyfuss + Blackford Architecture in Sacramento, says, in part, the dome communicates the building’s use to passersby, and the museum’s significance. “We wanted to be able to express the unique program from the inside of the building to the outside. We wanted the dome to be one of those beacons, something people would look at and say, that’s interesting. You don’t see that every day.”
In terms of its form, from some viewpoints, the curve of the dome, which is placed on an addition portion of the museum building, appears balanced with arched windows on the other half of the museum building, a renovated, historic power station built in 1912, PG&E River Station B.
“The dome plays off the arching of the windows; it’s very interesting you have this very rectilinear form of a building and then these little arches that play off of each other,” Holt says. “It really helps that planetarium sing, and it also shows how the historic and the new interplay at so many different angles.”
To clad the dome, Rua and Son Mechanical Inc. in Rocklin, Calif., fabricated and installed 0.8-mm-thick prePATINA zinc tiles in Graphite Grey from RHEINZINK America Inc., Woburn, Mass.
The flat-lock tiles gradually get narrower as they ascend the dome. The tiles are also tapered on each end to form to the dome’s curve, says Louie Rua, president at Rua and Son Mechanical. “Each tile tapers inward as they go up; this ensured the tiles stayed consistently tight to the shape of the dome.”
The tiles have a running bond pattern, which allows expansion and contraction of the tiles. Installing them on the dome required frequent adjustments to precisely align the tiles and make them tight against the dome. Over the course of a row, the ways the tiles interlock can cause them to slightly grow or shrink, called panel creep.
“Our fabricators/installers measured, laid out and installed about half the tiles needed for a complete ring around the dome,” Rua says. “After installing them, our team measured and cut the second batch of tiles to complete the ring, and adjusted sizes accordingly to ensure a consistent pattern as well as a tight fit to the curvature of the dome. You don’t get too far ahead at doing this to allow for inconsistencies in the dome frame too.”
Sacramento Municipal Utility District (SMUD) Museum of Science and Curiosity, Sacramento, Calif.
Size: 42,000 square feet (building)
Completed: April 2021
General contractor: Otto Construction Inc., Sacramento www.ottoconstruction.com
Architect: Dreyfuss + Blackford Architecture, Sacramento www.dreyfussblackford.com
Zinc distributor: Sheet Metal Supply Ltd., Grayslake, Ill. sheetmetalsupplyltd.com
Fabricator/installer: Rua and Son Mechanical Inc., Rocklin, Calif. www.ruainc.com
Roof underlayment: GCP Applied Technologies Inc., Cambridge, Mass. gcpat.com
Zinc: RHEINZINK America Inc., Woburn, Mass. www.rheinzink.us