New Orleans, Louisiana

Holbert Apple Associates provided structural engineering services for the renovation of the historic “Oil & Gas Building”, a 15-story office building located in downtown New Orleans, into a 170+ room hotel.  The existing structure, constructed in 1959, consists of a two-way mild-reinforced concrete slab and beam system at the typical floors and roof.  The existing lateral system utilizes concrete beam-column moment frames and the foundation system is made up of concrete pile caps supported on concrete caissons.

A key aspect of the Canopy Hotel program was the addition of a new rooftop terrace, which resulted in an increase in the dead and live loads on the existing roof structure.  The renovation also included the installation of new elevators and a new mechanical system that serves the entire building, requiring an increase in the height and footprint of penthouse.  To accommodate the areas of increased gravity loads, local strengthening of the existing structure was incorporated.  The increased penthouse height and area also resulted in an increase in lateral loads on the existing structure.  When the combination of increased gravity and lateral loads were considered, several of the existing beams and columns were found to require reinforcing.  Reinforcing was designed using several methods, including supplemental steel and fiber reinforced polymer (FRP) wrapping.

The historic one-story “One-Hour Cleaners” building, located adjacent to the Oil & Gas Building, was renovated into a bar/restaurant that is connected to and serving the new hotel.  A new three-story addition, for use as office space and other back-of-house functions, was also added to the rear of the “One-Hour Cleaners” building.  The new portion of the structure consists of composite steel floor framing, with steel columns and masonry bearing/shear walls.  Due to poor soil conditions, the new addition was designed to be supported by helical piles.  The existing “One-Hour Cleaners” building, however, was originally supported on conventional spread footings.  To help limit differential settlement between the existing “One-Hour Cleaners” building, the existing “Oil & Gas Building”, and new three-story addition; a system of helical piles and cantilevered grade beam underpinning was incorporated to support the “One-Hour Cleaners” building.

The building is listed on the National Register of Historic Places, due to its original façade that is classified as “Modular Grid Modern” and consists of mostly of glass with both horizontal and vertical bands of marble.  Although the structural design is complete, the reuse/reconstruction of the original façade is still being worked out and construction has not begun.