Workers have been seen doing interior work on the Mayfair Hotel on King Street.

The old hotel is slated to be redeveloped into an upscale boutique hotel and spa.

The plan would see a glass and steel addition to the top of the heritage building that would bring it to nine storeys. The renovated hotel could feature restaurants, a bar and a “speakeasy” club.

Ridgewood Holdings did not return calls for comment.