Structural Safety
Cracked Window at Troubled Millennium Tower Triggers More Analysis
Millennium Tower has sunk 18 in. and tilted 2 in. since it opened in 2009.
PHOTO BY NADINE M. POST FOR ENR
The 58-story Millennium Tower in the Transbay district of San Francisco, which has sunk 18 in. and is tilting 2 in., is under even more scrutiny for possible structural defects since a window on the 36th floor cracked. As a consequence of the damage, the city threatened to restrict access to the building, but it has since said it will “continue to monitor closely the situation.”
On Sept. 12, Ronald Tom, assistant director of the San Francisco Dept. of Building Inspection, sent a letter to the Millennium Tower Association saying failure to repair an inoperable window- washing crane, install pedestrian protection and conduct a field inspection “will result in a yellow tag of the building.”
Thomas Miller, an attorney for the homeowners’ association, responded to the city by saying, “It is our opinion that more likely than not, the issue which caused the glass break in unit 36B is isolated and not widespread.”
A report from Oakland-based architect-engineer Allana Buick & Bers is expected this week. The firm is surveying all units in the 645-ft-tall residential tower to look for cracked glazing and signs of curtain-wall damage.
The homeowners’ association received permission to hire an inspector to rappel down the side of the building to examine the cause of the crack and secure the glass from the outside. The city also ordered installation of a sidewalk shed to protect pedestrians.
William Strawn, the buildings department’s manager of legislative and public affairs, said demand letters were sent to accelerate a response to the situation.
A class action lawsuit filed in 2016, claiming the builders knew about the sinking when the tower opened in 2009, could go to trial as soon as next year.
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