Metro

Mortar-fying!

(James Messerschmidt)

Who knew they’d need hard hats with their afternoon tea?

A flood of liquid concrete burst through a lobby wall at the swanky Le Parker Meridien hotel yesterday — sending cafe patrons and $600-a-night guests fleeing out to West 57th Street.

“I was at the hotel having coffee with a friend,” said Bernard Gershon, 54, of the Upper West Side. “One second, I’m sitting there having a cappuccino and the next moment, we are running for our lives. It was crazy.”

Luckily, no one at the 727-room hotel was hurt when the concrete began to flow at around 11:30 a.m.

The accident happened when a wooden retaining wall broke on the fifth floor of an unrelated, 29-story hotel construction project next door. a hard hat told The Post.

With the wall breached, tons of liquified concrete sloshed into the Le Parker Meridien.

Hotel workers rushed into action, hauling out wheelbarrows of concrete before it hardened. They also hosed down velvet-cushioned chairs, tables and lush oriental carpets on the sidewalk outside.

City inspectors will determine if the concrete retaining wall was properly built, a Department of Buildings official said.

The DOB slapped the site with a stop work order. Inspectors had issued a partial stop work order Tuesday against contractor DiFama Concrete for employing an unlicensed crane operator on the job.