"This is a window system that's designed to sustain hurricane force winds so this is obviously of serious concern," said San Francisco Supervisor Aaron Peskin.
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The city's Department of Building Inspection shared photos of the crack with ABC7 News.
Tom Miller, the attorney for the homeowner's association says the person who lives in 36B heard a loud pop during the middle of the night over the holiday weekend.
Miller says the outside pane of glass cracked.
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"The problem on the exterior is that glass going to hold or is it going to be a falling object," said Miller.
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The Department of Building Inspection tells ABC7 News an inspector has been to the site 3 times, including Wednesday afternoon. That inspector determined there is no imminent risk to pedestrians below, specifically because the glass is laminated and designed to hold in place even when fractured.
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The city issued a correction notice letting building management know they have until Friday to issue a report including an evaluation of the repairs needed.
Miller says a new window has been ordered and will be installed within a week. During the replacement he says they'll open up the side of the building to investigate what caused the crack
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The building's manager sent a notice to residents saying it's possible the incident is related to other issues in the building but Miller says a seismic expert and structural engineer disagrees.
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"He informed us that it appeared not to be related to the performance of the building sinking or tilting," said Miller.
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As for those problems, the Homeowner's Association President says they are considering alternatives to bring the building up to the highest standard.
"Now it's really a question of the legal process to find the responsible parties to pay for and implement the fix," said Steven Mayer, Homeowner's Association President.
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