A painted movie advertisement from the 1920s that was uncovered during a building demolition in downtown Vancouver Thursday cannot be salvaged, according to the architecture firm responsible for the project.

The hand-painted ghost ad, promoting the Howard Lloyd-starring 1922 film "Grandma's Boy," features a floating hand pointing pedestrians across the street to the since-bulldozed Capitol Theatre. The movie ran for five days.

Mark Thomspon of Musson Cattel Mackey Partnership said the faded ad was a surprise discovery, and will be "basically impossible to save."

"The brick façade is not up to the current seismic code so it's very difficult to integrate it into the new structure," Thompson said.

The ad will be photographed, however, and the building that goes up in the space on Granville and Robson streets – a full-block retail and office development – may integrate the images into the lobby's interior design.