A 74-year-old woman was killed outside of her Brooklyn townhouse when brick crumbled off the building and came crashing down on her, police said.

Dale Singer was leaving the townhouse on Sixth Avenue near 54th Street in Sunset Park around 12:30 p.m. Tuesday, police said.

As she locked the door, a large chuck of concrete molding came loose and fell on the elderly woman’s head, police said.

Arriving cops administered CPR to Singer, and she was taken to the Maimonides hospital in critical condition. She was later pronounced dead, authorities said.

Police have notified the Department of Buildings, which will now conduct its own investigation.