Mount Sinai Behavioral Health Center Conversion

The Mount Sinai Health System (MSHS)’s new Behavioral Health Center conversion of a former HIV/AIDS nursing home will retrofit the original structure into state-of-the-art community-focused health complex. Accordingly, the new healthcare facility will serve as a ‘one-stop’ location of services for mental health, addictions, physical health and social-service.

The existing building located at 45 Rivington Street in New York City consists of a main five-story unit with a small adjacent one-story structure. Constructed in the early 1900s, terracotta slab floors and cast-iron columns are found throughout the main building. Additionally, there is a full footprint cellar and a penthouse level which occupies a portion of the roof.

Therefore, to best complete a retrofit conversion, the new Mt. Sinai behavioral healthcare facility began with a full gut renovation. Consequently, this included select structural demolition, new MEP infrastructure, and new elevators.

McLaren Engineering Group provided structural engineering, façade investigation, and civil engineering services for the conversion and retrofit.

Detailed Facade Investigation

First, we began with a visual observation of the exterior facade. All findings are documented in a written report that included typical facade deficiencies and repair recommendations.

Structural Engineering – Retrofit Conversion

Existing Conditions

Next, McLaren performed an existing conditions survey where retrofit structural and mechanical upgrade points. After reviewing structural and architectural drawings and comparing information to as-built conditions, the team identified locations that required additional probing to verify conditions.

Building Conversion Design

For the conversion design, we developed framing concepts. Additionally, we reviewed alternate schemes and developed concept details for any facade work. We provided an assessment of construction materials and systems. Next, the team prepared a written narrative describing results and the structural basis of design. The narrative included a description of the proposed structural systems and preliminary member sizing and sketches to convey the overall concept. Structural service components for the Behavioral Health Center conversion included:

Terra-Cotta Slab Repairs

Deficiencies in the existing terra-cotta slab construction required remediation. As such, McLaren performed an investigation and provided a probe plan to further investigate some of the regions of unknown condition. Next, we developed a structural repair package to for necessary replacements and repairs.

Elevator Upgrades

For the existing floor framing, we developed shaft way openings and modifications. Additionally, the team provided design for the modified loading created by the elevator equipment and machinery for the new elevator core and two new service elevators.


McLaren provided engineering for the two new canopies for the conversion. This included attachment to the building structure and review of the building to receive the loads.

Support of MEP Upgrades

Additionally, MEP infrastructure upgrades were serviced. For instance, the team helped to develop typical mechanical equipment support details. Additionally, a load rating analysis of the existing rooftop dunnage and the roof level framing to support were performed for the final proposed mechanical equipment. Also, McLaren designed maintenance pads and dunnage, as required. Lastly, we designed openings in existing slabs for new shafts and design of infill for existing openings or shafts no longer required.

Civil Engineering Services

Utility Services Evaluation

Our team coordinated with the MEP Engineer regarding testing of existing utility services and determining which services would be protected or replaced. Additionally, we assisted in obtaining a video inspection consultant to determine the condition of the existing sanitary discharge pipe.

Utility Plans

McLaren worked with the MEP Engineer to produce Utility Plans for all work occurring five feet outside of the building. Plans included water, gas, electric, and sewer lines.

Permit Drawings

Additionally, we provided drawings and services to obtain the required permit approvals for renovation of the sidewalk adjacent to the building.

Construction Administration Phase Services

Finally, we reviewed civil shop drawings/submittals and responded to RFI’s regarding the civil project scope.

Award Winning Project

In 2023, Association of Medical Facility Professionals (AMFP NYC) awarded Mount Sinai Health System Sinai Beth Israel Behavioral Health Center Project of the Year in Over $50M category.