Building Statistics

Towson University’s West Village housing project phase III & IV consists of two, multi-story, high-rise apartment buildings and the related site work. These buildings will be used as residential halls with 4 single bedroom and 2 single bedroom apartment configurations. The layout of the residence halls includes private and public areas with study and community lounges on each floor. Within each 4 bedroom set is a shared living area creating a home like community within each space. An additional community space is created outside, between both buildings with a central lawn for student events and recreation. The exterior of the building is faced with brick facades that are divided by flush metal wall panels adding personality to this area on campus. The addition of these two buildings not only adds students directly into campus life but also helps connect scholars to the educational buildings of the University.

Historical Requirements

Historical requirements are not applicable for this

project

Codes

The major national model codes for this project include: International Building Code 2012 with the Department of Housing and Community Development (DHCD) modifications, ASCE 7-10, IBEC 2009, IEBC 2012, IRC 2012, IPC 2012, IMC 2012, MAC 2011. The project is following Baltimore County zoning laws.

Facade

The main façade of the two buildings are layered from exterior to interior with 4-in veneer brick, SST flashing with end dams at window sills, 2-in air space, 2-in of Polyisocyanurate Board insulation, glass mat gypsum sheathing, 6-in cold formed structural steel stud framing back up and interior gypsum board. Other sectioned areas on the exterior of the building are faced with metal composite wall panels with sealant joints in replace of the brick to add contrast to the overall façade. Metallic faced sheet membrane tape is provided at all joints between cladding materials and at all penetrations in order to seal the air barrier. Three main window systems make up the exterior of the buildings. They include: operable casement units with thermally broken aluminum framing and full screens, steel reinforced storefront window systems with insulation and 1-in insulating glass, and glazed aluminum curtain walls. The store front window systems are used at the main entry foyers of the building to allow light through and open up the space.

Roofing

The main roof systems consists of rigid insulation topped with Thermoplastic Polyolefin Roofing (TPO). A lower portion of the roof on both buildings is made up of a green roof system. The system contains rubberized asphalt membranes fully adhered to concrete deck with extruded polystyrene insulation. Stainless steel sheet metal flashing and trim are used throughout the roof as well as silicone sealant for joint sealers.

Sustainability Features

The two new residence facilities will be built in adherence wiht sustainable design and construction standards and are expected to achieve LEED certification. Some sustainable features that are to be integrated into the design, consist of efficient mechanical and electrical systems. The mechanical system includes variable volume air handling systems as well as variable flow chilled and hot water systems with variable speed pumps. Dual wheel energy recovery systems will also be incorporated for the buildings exhaust air. High frequency ballasts and lamps will make up the lighting/electrical system. Occupancy sensors will be installed in all occupied spaces and centralized lighting controls for corridors. In addition, there will be active day-lighting controls in large public areas.

Click to enlarge roof details. Image courtesy of Ayers/Saint/Gross Architect and Planners

Image of new buildings adjacent to central lawn, courtesy of Towson University Construction Services

Primary Engineering Systems

Structural

The foundation of the structure is supported by concrete columns and Rammed Aggregate Piers (RAPs) in order to utilize conventional spread footings and foundation walls. This is due to the insufficient existing soil conditions. RAPs are vertical underground layers of compacted aggregate that uses a ramming action to produces lateral prestressing in the adjecent soils. These piers are designed for an allowable bearing pressure of 5 ksf. The column footings vary and are to be at least 16 inches wide for shear considerations and are placed at least 30 inches below final exterior grade for frost protection. At the east end of the north building, up to 15 feet of the wall is below final exterior grade. Therefore, permiter walls are required and are to be 12 inches thick reinforced with with #5@12” vertical bars on each face and #4@12” horizontal bars on each face supported by a continuous wall footing.

West Village Housing's North Building is a concrete structure utilizing an 8” thick two-way post-tensioned concrete flat plate system supported by concrete columns. All columns are 24"x24", reinforced with (8)#9 vertical bars, and extend throught the entirety of the building. The slab is reinforced with ½” diameter un-bonded tendons in each direction and mild reinforcement, as required, in other locations. The average pre-stress force in the slab shall be 18kips/ft in each direction and the average weight of mild reinforcement shall be 2.5lb/s.f. For the majority of the building, banded tendons run along the long axis of the building with uniform tendons running perpendicular.

The Lateral Force Resisting System (LFRS) of West Village Housing North Building consists of 10 regular concrete shear walls that are 12” thick. They are located at the East and West ends of the building to effectively resist the forces imposed on the building due to the wind and seismic loads. All stair and elevator walls are concrete shear walls with an average weight of reinforcing of 7 lb/s.f. The reinforcement in each wall consisted of #5 bars at 12” O.C. both vertically and horizontally.

Electrical/Lighting

For the primary distribution system, the utility company's system will serve a pad-mounted transformer at each building. The primary feeders will originate from the utility site sectionalizing switches located adjacent to each building. Normal power for the building will originate from the pad-mounted service transformers. Service to the building will be 480/277 V, 3-phase, 4-wire, wye connected, grounded neutral. Each floor will have one distribution panel, sized accordingly to feed all dwelling units on the associated floor. The wiring will be insulated conductors installed in raceways.

Generally, interior lighting will be fluorescent type T5. Downlights and decorative fixtures will be LED. LED stencil face aluminum or recessed edge-lit type exit signs will be used. Fluorescent and LED sources will be provided with electronic type ballasts/transformers. Lamp color temperature will be 3000 K for a warmer, residential feeling. Automatic control devices will be provided to shut off building lighting in all spaces. Each space will have an occupancy sensor to independently control the general lighting within the space.

Mechanical

The heating of the building will be provided by high efficiency gas fired hot water boilers. a hot water system that consists of two boilers, hot water pumps, and piping. The hot water plant will be located in the penthouse on the roof. Chilled water will be distributed to coils in individual fan coil units via vertical distribution for each suite. The chillers will be water-cooled, rotary screw type with very high energy performance to deliver 44 degree chilled water. Energy Recovery Units (ERU) will be single-zone medium pressure type to provide air conditioning. They will be located on the roof, and serve all spaces requiring ventilation that are served by individual air conditioning units. Outside air will be introduced into each unit through exterior wall louvers. In addition, all units have occupant operable windows.

Construction

The University of Towson has contracted with Whiting Turner Contracting Company to provide pre-construction services during the design phases, and to be the Construction Manager at Risk during construction. The buildings began construction simultaneously in September of 2014 to address the continued demand for on-campus housing. They are planned to be finished in the summer of 2016 before the following school semester. Clearing and grading of the site was minimal due to the fact that the present site condition at the time existed as two surface parking lots. The total budgeted cost of the project is being withheld at the request of the owner.

Fire Protection

The north and south buildings will be protected throughout by a combined system of Class I manual, wet standpipes and automatic sprinklers. System will comply with all local codes and are designed to meet the International Fire Code, 2012 edition. Piping will be sized by hydraulic calculations. Mechanical rooms, electrical rooms and storage areas will be classified ordinary hazard Group 1. Maximum area per sprinkler is 225 sq.ft. A combination of wed sprinkler/standpipe risers will be located within each stairwell. Water supply for each building will consist of 2 separate incoming fire service feeds from connection to the campus mains near the building.

Security

Card readers and door monitoring will be provided on all extior doors as well as doors leading from publically accessible spaces. All card readers will be connected to the access control system field panels in the building. These in turn, will be connected to the existing campus access control system via the campus data network. Cameras designed for video surveillance will be IP cameras meeting the current Towson University standards and will connect to the video managment system via the campus data network. In addition,

West Village Housing Phases III & IV

Towson University, Maryland

Mark A. Bland

Architectural Engineering [Structural Option]