Name: Race Street Dormitory, Drexel University
Location: 3300 Race Street, Philadelphia, PA
Building Occupant: Drexel University Students
Occupancy Type: Dormitory
Size: 132,800sf
Number of Stories above Grade: 12

Primary Project Team
Owner: Drexel University, Philadelpha, PA
General Contractor: Intech Construction, Philadelphia, PA
Construction Manager: Intech Construction, Philadelphia, PA   
Architects: Erdy McHenry Architecture, Philadelphia, PA
MEP Engineer: Indoor Quality Solutions, Erdenheim, PA
Structural Engineer: Cagley Harman & Associates, King of Prussia, PA
Civil Engineer: Pennoni Associates Inc., Philadelphia, PA
Dates of Construction: June 17, 2005 – February 26, 2007 (scheduled)
Actual Cost Information: $22,000,000 (estimated)
Project Delivery Method: Design-Build

Architecture

The dormitory is basically an ‘L’ shaped building, which veers slightly off the right angle. At its lowest level above grade, only part of one leg of the ‘L’ shape runs east-west. This ground level consists of mechanical rooms, electrical room, and maintenance rooms as well as a shop and bicycle room. This floor is abutted against a higher grade (one story) which creates the grade for the other wing of the building. The first floor lies on only the footprint of the ground floor and contains the main entrance lobby (entrance from the higher grade), mail room, Resident Assistance suite, and multipurpose room. The second through eleventh floors sit on the first floor and bend north to complete the rough 'L' shape. These floors contain 130 student suites for 490 students. Each suite contains two bedrooms, a living room, bath room, and kitchen. There are also two common rooms on each of these floors. The north-south wing of the second floor rests on free standing columns between the first and second floors creating an open air patio area under the building at part of the fiFebruary 16, 2007ner in the building, two of which begin at the first story level. There are two stairways at the far north and east ends of the building.

Structure

The residence hall is a steel W-shaped column and beam frame with moment connections, moment frames, and braced frames. There are six braced frames and two moment frames. The floor heights are 9’4” for floors two through eleven, 14’ for level one, and 10’ for ground level. Each floor consists of pre-stressed pre-cast hollow core concrete planks 8” deep, typically 8’ wide with 2” cast-in-place concrete topping. The planks are typically 22’8 or 28’2” long (8” overhang typical). Beams run predominately longitudinally along the building, as floor planks span two horizontal bays. Beam sizes are mainly W12 or W18, and span up to 30’8”. The third through eleventh floors have identical beam systems, while the beams at the first and second floors are unique and generally larger. The roof is flat and consists of mainly W12 beams spaced 6’ on center and Grade 33 structural galvanized steel decking supporting EPDM single-ply membrane roofing over rigid insulation.

Envelope

The ground floor is a slab on grade with exposed concrete walls on the exterior of the steel framing system. The walls of the first floor and corners of higher floors have an aluminum curtain wall with virtually floor-to-ceiling glazing. The majority of the facade between the second floor and roof is made of cold formed steel studs with corrugated, ribbed, and smooth aluminum, steel and alloy-coated steel sheets as exterior sheathing with strip glazing. The roof is steel decking with EPDM single-ply membrane roofing over rigid insulation, and stairwells are brick on steel studs.

Mechanical System

The residence hall has a fan driven air volume system with individual air systems and water source heat pumps in each suite. Outside air is supplied by a rooftop unit of 8725 CFM via one general diffuser in the hallway of each floor, and then pumped into each suite’s room for heating.

Lighting/Electrical System

The Race Street Dormitory is fed 15kV of electricity via Calhoun Hall, a nearby residence hall. An initial transformer feeds to dimming panels on floors two through eleven with a 120/280V 3 phase 4 wire system. The first transformer also branches off to another which supplies the lighting on the ground and first floors (no dimming), the mechanical systems for the entire building (277/480V). In the event of emergency, an onsite generator is available (480/277V).

Zoning

The building covers 12,140 sq ft and the required parking is 1 per 4000 sq ft, or 33 parking spaces. The building is set back 7 ft from the southern road (Cherry ST) and 13 ft from the east and north roads (33rd ST and Race ST). A 20,853 sq ft square lawn area fills the north-east corner of the “L” shape, at roughly ground floor grade.

Codes

2004 Philadelphia Building Code (IBC 2003)
ASCE 7 - 02
ACI 2001