Updating a Historical Landmark
Once considered Wilmington’s first “skyscraper,” the original six-story masonry building at 901 North Market Street was first constructed in 1892. Subsequent additions in the early 1900s added the seventh, eighth, and ninth stories. Renovations to the building and a 14-story addition were added in the late 1950s, along with a metal façade over the original masonry. The new renovations and upgrades have transformed the property into a contemporary mixed-used building that provides multiple retail spaces and artfully constructed apartments in the heart of Downtown Wilmington.
Due to the historical nature of the building, the design of the renovation had to be approved by Historical Preservation Wilmington, which imposed restrictions on what changes could be made to the exterior of the building. Great care was taken to preserve and integrate historical elements while making the necessary updates, striking a balance between respecting the building’s historical significance and incorporating modern design and functionality.
A new facade was added to compliment the historical character of the building. New windows were installed throughout to improve energy efficiency and increase natural light. Exterior lighting highlights and enhances the new façade at night while improving the building’s visibility, safety, and overall aesthetics.
Investigation of the existing conditions can sometimes uncover unexpected features of the original construction that can be incorporated into the new design. In this case, there were existing structural brick arches discovered behind walls that could be left exposed as part of the new apartment finishes. Other features included the reuse of bank deposit boxes, mailboxes, cast iron columns/steelwork, and other historical features. An old air shaft and an adjacent floor-high steel truss were transformed into a two-story atrium in the center of the building, including a massive skylight.
Overcoming Obstacles
The overall building structure was divided into two sections. The nine-story section consisted of the original six stories from 1890, and the seventh, eighth, and ninth-story addition from the early 1900s was a wood structure with masonry foundations. This was adjoined to a 14-story section added in the 1950s constructed with concrete and steel.
The overall structure of the building contained different building standards across each floor due to the differences in construction techniques utilized throughout its history. For example, the building mechanicals for the wood side did not match up with the steel side. Due to the tapered structure on the masonry side, systems like the plumbing often did not correctly line up and stack from one floor to the next. Trying to marry all the floors and the different techniques used on each side was challenging. The final product needed to be seamless from one side to the other and from floor to floor.
The original design included a rooftop deck on the tenth floor (ninth-floor roof). Eventually, that idea was dropped during the value engineering phase of the design. However, the owner discussed adding a rooftop deck back to the project once construction was underway. The original layout was not feasible due to issues with the location, such as mechanical systems that needed to be installed, load calculations, and other factors. The deck location needed to be modified and distributed once the tenth floor was complete. The team skipped construction on the building’s ninth-floor wood and masonry side to accommodate any revisions needed for the deck. This meant that all the units on that side from the ninth floor down could not have the plumbing or the finishes completed because they needed to tie into the new rooftop deck plumbing. Also, during the investigation for load support, the team found the support under the penthouse for the deck to be inadequate. The roof beam was sitting on old brickwork from an elevator shaft and could not support the deck. Wohlsen had to engage the structural engineer and added steel supports from the ninth-floor roof support all the way down to the first floor.
A Tight Urban Setting
One of the biggest challenges this project presented was its location within the heart of downtown Wilmington. We were essentially working on a postage stamp, as we like to call it. There was no space. Parking, staging, and laydown areas were practically non-existent. Construction on one floor was happening simultaneously with demolition on another floor. Laydown space was minimal. On-time material deliveries had to be tightly coordinated because there was no extra room for storage. This challenge was compounded by industry-wide material shortages and the long lead times required for purchasing.
Bringing New Energy to Downtown
The transformation of this historic building did not come to fruition without some significant challenges. However, the collaboration and teamwork exhibited by the owner, design team, and Wohlsen Construction to devise and implement creative and effective solutions. The 901 Market Street Tower renovation project successfully repurposed the historic building into a contemporary space, showcasing a blend of history, modern design, and functionality that brings new energy to the Wilmington Downtown District.
