Architect of Record: Ryan Companies US, Inc.
Design Architect: Humphreys & Partners Architects
Structural Engineer: Meyer Borgman Johnson
Total Project Cost: $57.3 million
Total Project Size: 580,000 sq ft
Award: 2012 CRSI Merit Award – Residential Building Category.
Photography: Three Line Studios
The project goal for 222 Hennepin was to create the ultimate urban mixed-use development with upscale amenities and a focus on sustainability. 222 Hennepin is a 580,000 square foot, seven story mixed-use development containing 286 upscale apartments and anchored by the first Whole Foods Market in downtown Minneapolis. 222 Hennepin is situated on (the former Jaguar Land Rover Dealership site at the corners of Washington and Hennepin Avenues) one of the most prominent corners in Minneapolis.
Ryan Design worked with Humphreys & Partners Architects on the conceptual design of the project, which focused on balancing the housing needs of sophisticated, discerning apartment residents with the commercial needs of a top-tier urban grocery store.
Ryan is also the architect-of-record and builder for the project. This project essentially jumpstarted the apartment/condo boom in the areas closer to the core of downtown Minneapolis.
Along the way, the Ryan team was able to find reuse of the parking ramp structure that remained on the site and through the use of creative structural engineering and design we were able to take this project from conception through to completion in near record time getting our project out to market before all of the other housing projects in nearby neighborhoods could deliver. They were also able to provide creative structural engineering solutions that incorporated cast-in-place concrete and reinforcing steel to be able to deliver an efficient, yet robust structure that will serve the residents of this neighborhood and the City of Minneapolis for generations to come.
Project amenities include a fourth-floor terrace with an outdoor pool, bocce area, fire pit, state-of-the-art fitness center, Jaguar Room with wine storage, cyber café, and more. The terrace itself affords spectacular views of the downtown Minneapolis skyline and the Mississippi River.
STRUCTURAL FRAMING SYSTEM
EXISTING PARKING STRUCTURE: The existing four story, conventionally-reinforced parking structure was constructed in the mid-1960s. This structure was adapted for the 222 Hennepin project for use in tenant parking and support of housing above. The existing structure exhibited various degrees of deterioration, which required restoration. The structure was modified to remove the existing fourth level and add a post-tensioned concrete podium. The structure was strengthened, including adding new concrete shear walls, to provide gravity support for the new housing above and lateral support of housing and retail components surrounding the parking structure.
RETAIL SLAB (Whole Foods): The retail grocer tenant required a structure floor solution to simultaneously support heavy super-imposed loads, provide flexibility for over 400 sleeve penetrations, have a shallow floor-to-floor depth to the lower level below (dictated by the existing adjacent parking structure), and meet code-prescribed fire resistance requirements. A conventionally-reinforced, two-way flat slab with flexural drop capitals was selected as the optimal system to meet these criteria. The slab system is designed to support an unbounded 5 inch topping slab and 125 psf superimposed live loads. Portions of the formwork were strategically cambered to mitigate effect of long-term slab deflections due to creep. All needed slab penetrations were successfully located and placed.
PODIUM SLABS: New structured slabs were designed to support up to five-stories of new housing. Two-way, post-tensioned concrete slabs were chosen for their strength and deflection performance and to address shallow floor-to-floor heights. Special detailing was used to permit concrete shortening due to post-tensioning while permitting the diaphragms to tie-in to the existing parking structure for lateral resistance. PT slabs were folded or stepped, as needed, to conform.
REASONS FOR CHOOSING REINFORCED CONCRETE
Working Toward LEED Silver Certification for Midrise Residential, the Team Incorporated the following Sustainable and Energy-Saving Elements:
- Utilizing the existing 300-stall parking structure remained in place, which saved in excess of 20 million pounds of concrete, over 1 million pounds of steel reinforcement (rebar) that would have been used to replace it, and drastically reducing the demolition waste that would have been generated.
- Extra measures have been taken to seal the units to reduce air leakage which will lower the risks of indoor air pollutants, as well as making the building 100% smoke-free.
- Off-site fabrication of the interior roof, walls and floors minimized the waste created on-site. In addition, approximately 65% of the construction waste was diverted from landfills through recycling programs.
- Cleaning up, reinvesting and redeveloping an urban brownfield site of contaminates protects the environment and reduces blight.
- Downtown location encourages the use of public transportation, as well as bike and foot traffic reducing emissions. In addition, the compact, amenity-rich site promotes community living.