Building Name: JW Marriott
Location/site: 187 Monroe N.W., Grand Rapids, MI  49503/ Urban
Occupancy type: Hotel
Size: 376 000 square feet
Total Stories: 24(high rise)
Primary project team:
            Owner: Alticor Inc. – HP3, LLC.
            General Contractor: Rockford Construction Co. and Pepper Construction Group
            Architects: Goettsch Partners and BETA Design Group
            Engineers: Thornton Thomessetti - Structural
                              Cosentini Associates- MEP
                              Fishbeck, Thompson, Carr, Huber, Inc. – Civil/Environmental
Construction Dates: June 2005 – Sept 4, 2007 (tentative)
Overall Project Cost: $95 million. Hard cost; does not include FFE or OSE.
Project Delivery Method: Design-Bid-Build
Building Codes: IBC 2003
Historical Requirements: None
Zoning: R-1. Residential.
Building Envelope: Glazed curtain wall encases the hotel. Precast concrete with
                                    intermittent glazing encases the parking garage.

Building System Descriptions:

Architecture: Designed to maximize the views without disrupting the views of the Amway Grand tower, this glass clad tower does not detract or outdate any of the Grand Rapids skyline. The resulting shape creates a strong presence in the otherwise conservative downtown skyline and has energy savings due to lack of pure south facing rooms. The absence of perimeter columns creates large aesthetic benefits that maximize views.  The JW Marriott will be a multi-use development including a Parking Garage, Business Center, Restaurant/Lounge, and Fitness Center. The level of service is planned to match that of any Grand Rapids hotel but will do so with a nationally flagged hotel.

Project Delivery:

The project delivery method is complicated in parts due to the unique circumstances surrounding the project. Only trades such as fire protection and piping and irrigation utilize a design build method. All other trades were bid out and awarded based on multiple reasons that did not only focus on low cost. Prior client relationships, most qualified, and locality were influential for subcontractor approval. The construction management team is participates in a joint venture with a local company, Pepper Construction is under a construction management contract structure with the owner. Pepper was awarded the job on a negotiated basis and is locked in on a price for general conditions and fees.

Structural System:

Foundation:
The foundation of the JW Marriott consists of multiple parts. A slab on grade covers the entire basement with 6 inches of 4000 psi concrete reinforced with WWF and 10 inches of 4000 psi concrete reinforced with 4#12 bars each way in the loading dock area. Grade
beams travel between the building elevator core pile caps. The grade beams range in size from 16-28 inches wide by 42-48 inches in height. All grade beams are 6000 psi concrete reinforced top and bottom. Along the perimeter of the tower there are 21 piles that consist
of (4-7) 200 ton micropiles. Each micropile drives 19’ into the ground. In the elevator core there is a cache of micropiles, (94) 200 ton. Just outside the elevator core there are two groups of 8 micropiles, one of each side of the core in the North-South direction.

Framing System:
The repetitive tower framing plan offers a distinct advantage to the structural engineer and general contractor. The typical framing plans take affect from floor 5 through 23. On the first and second floor there are 21 reinforced concrete columns, 24 inches in diameter.
The concrete in the columns change from 10 ksi to 8 ksi to 6 ksi at the sixth and fourteenth floors, respectively. Above the fifth floor the number of circular columns is reduced to four. In the guest rooms, columns are replaced by a series of 10 inch thick
wall-columns to maximize views. The elevator core offers support for the interior of the structure.

Floor System:
The existing floor system of the JW is a oneway reinforced concrete flat plate from floors 5 through 22. The slab is 7.5 inches thick and uses 5000 psi strength concrete (unless otherwise noted). Fourteen openings in the slab, located in the main corridor, allow for mechanical duct access. The overall shallow depth of the system permits greater flexibility for the architect’s interior design. Throughout the guest levels code specifies 40 psf live load. The size of the typical bay is a trapezoid with vertical lengths 10’-7” and increasing to 17’-9” and a horizontal length of 35’-3”.

Lateral System:
Concrete shear walls and will serve as the primary lateral force resistance. Located within the elevator core, the walls will span from the basement to the helipad. Two major pairs span in each direction (two 25’-6” walls in the East-West direction and in the North-South direction a 35’ and a 10’-7” wall). All shear walls are 12 iMay 1, 2007 from the wall-columns placed along the exterior of the JW Marriott. These walls are typically 11’-8” wide and 10” wide. The wall-columns are staggered at angles ranging from approximately 45-78 degrees from vertical. The concrete used in both shear walls and wall-columns vary with height above grade from 6 to 10 ksi.

Electrical/Lighting System:

The distribution to the JW Marriott hotel can be found at both 480/277 and 208/120 volts. Guest room voltage is at the lower, 208/120 volt, power level. The service demand load for the structure is 431,730 VA. The power travels up the tower in a 1600A 480/277V busway. At every third floor in the tower a 300kVA transformer converts the power to guest room levels. There are four 208/120V 100A emergency lighting switchboards throughout the hotel to guide patrons in the event of an emergency.

The lighting system for the JW Marriott has yet to be designed. The system is being designed as the structure is going up.

Mechanical System:

The variable volume mechanical system is located on the 24th floor, aptly designated the mechanical penthouse. The atrium and guest rooms use 100 percent outdoor heat recovery from two air handling units within the mechanical penthouse. The guest rooms are supplied with over 23,000 cubic foot per minute of air and the atrium is supplied with over 15,000 cubic feet per minute of fresh air.  Safety is provided against the harsh winter months of Grand Rapids by using snow melting zones. Located beneath the helipad, driveways, and walkways, the mechanical system supplies patrons with over 42,000 square feet of snow free area.