SF supervisor questions Millennium Tower cracked window investigation findings

SAN FRANCISCO (KGO) -- San Francisco Supervisor Aaron Peskin is calling for an independent review of the cracked Millennium Tower Window after a firm hired by the Millennium Tower Homeowner's Association issued a report saying the crack was caused by an exterior impact, unrelated to building movement and settlement.

New photos of the cracked 36B Millennium Tower Window are part of a report from Architectural Engineering Firm Allana Buick and Bers. ABB conducted an investigation and found the crack was from a source break due to exterior impact and unrelated to building movement and settlement.

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"What are they talking about," said Supervisor Peskin.

Peskin questions the conclusions and credibility of the report.

"It's one of these there's nothing to see here, everybody move along reports."

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The report references an interview with the homeowner after Labor Day weekend when the window cracked. The homeowner described being awoken by a massive bang at 2:30 in the morning.

"This sound was so massive in scale, it sounded like a huge, thick vault door had just slammed shut," said the homeowner in that interview.

The homeowner also described hearing a sound like glass cracking for a half hour following the bang.

"Is that a bird strike? Did someone shoot it with a gun from 36 stories below? Did it get hit by a drone? They have no evidence whatsoever," said Peskin.

This afternoon the HOA submitted a second structural engineering letter from LERA to the Department of Building Inspection stating there was "no indication building settling was the cause of the window cracks."

The Department of Building Inspection told ABC7 News its engineers are reviewing the information and that DBI has no comment at this time.

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"What I want is for our Department of Building Inspection to commission their own independent study," said Peskin.

ABB is recommending the pedestrian protection can be removed and that a further structural investigation of the curtain wall assembly is not warranted.

In the meantime, the pedestrian protection remains. It is something the Department of Building Inspection had required. It's not clear when DBI will respond to the findings of these reports.

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