Calder's 51-Foot Senate Sculpture Regains 4 Clouds in $12 Million Restoration

Q: Why did restoring Calder’s “Mountains and Clouds” require brand-new carbon-fiber clouds instead of simply rehanging the originals?

They needed new carbon-fiber clouds because the original suspended elements were judged unsafe to put back up, and engineers used lighter, stronger replacements to meet modern structural requirements while preserving Calder’s design. After the 2011 earthquake, the cloud portion was removed for study and lowered in 2014. Subsequent analysis found structural problems in the original mobile, which had been heavy and not suitable for straightforward reinstallation over the Hart atrium’s marble floor and skylights. Supporters of the restoration also said Calder never supervised the final 1980s realization of the work because he died in 1976, and there was evidence the clouds as built may not have matched what he intended. The restoration team therefore did not simply rehang the old pieces. Instead, it recreated the clouds in carbon-fiber composite, a material that could closely match the original appearance but weigh far less and satisfy current safety standards. The new sections are only a few inches thick and were engineered for long-term stability in the atrium. That approach solved two problems at once: it reduced the risk posed by the overhead mobile and allowed the sculpture to be restored in a form closer to Calder’s intended balance between the fixed steel mountains and the suspended clouds.

2 articles · Updated · The New York Times · Sep 30

Four newly made carbon-fiber clouds were hoisted back into Alexander Calder’s “Mountains and Clouds” in the Hart Senate Office Building, restoring the work’s original suspended elements after 12 years.
The replacement pieces are part of a $12 million renovation funded by two private donors, with contractors installing thin black slabs above the sculpture’s steel mountains in the atrium.
Capitol Hill officials had the original clouds removed after safety concerns emerged over the work’s structural integrity following the 2011 earthquake, leaving the sculpture incomplete.
The 1986 installation was Calder’s final work, and advocates had argued that removing the mobile clouds effectively mutilated the artist’s intended design.