Phil Mackey

A downloadable copy of the building statistics is available here.

Building Statistics

Building Name:
     Holy Cross Hospital - North Addition

Location:
     1500 Forest Glen Rd.
     Silver Spring, MD

Building Owner:
     Holy Cross Hospital

Occupancy Type:
     Institutional

Size:
     75,000 sq. ft. new work
     44,000 sq. ft. renovation work
     15,000 sq. ft. fit-out work

Number of Stories: 4+basement

Primary Project Team:
     Owner - Holy Cross Hospital   www.holycrosshealth.org
     Architect - Smithgroup   www.smithgroup.com
     MEP Consultant - Leach Wallace Associates   www.leachwallace.com
     Structural Engineer - McMullen & Associates   www.jjma.com
     Civil Engineer - Dewberry & Davis   www.dewberry.com
     Construction Manager - Bovis Lend Lease   www.bovislendlease.com

Dates of Construction:
     April 2004 - July 2005

Project Cost:
     Total Construction Cost - $21.9 million
     MEP System Cost - $7.8 million
     Structural Cost - $3.1 million

Project Delivery Method:
     Design-Bid-Build

Architectural Features:
     They added a new concourse and conference center on 1st floor, new obstitrician exam rooms on 2nd floor, new gynecological exam rooms on 3rd floor, and a fit-out on the 4th floor. Also, part of the existing hospital on 1st floor was renovated into a new outpatient center.

National Code Followed:
     IBC 2003

Zoning:
     There are no specific zoning concerns on this project.

Historical Requirements:
     There are no specific historical requirements concerning this project other than it has to tie into the existing hospital.

Building Envelope:
     - glass facade on concourse/atrium
     - tower is steel construction with cavity walls
     - cavity walls are efis
     - roof is flat steel decking

Construction:
     The contract was quite unique for this project. Since Bovis and many of the subcontractors were already working on the new Emergency Department renovation, the hospital decided to treat the North Addition like a giant change order. However, it can be considered a design-bid-build, only the bidding was done by a single contractor. Also, the landscaping of the exterior and ground work was contracted out as a separate package.

Electrical:
     Due to the importance of uninterrupted power to numerous components of a hospital's electrical systems, extra care was taken when designing the North Addition's power distribution system. In addition to normal power being run through the new wing, three emergency power systems (life safety, critical, equipment) were added to match the electrical system in the current hospital and to ensure all necessary equipment is running in case of an emergency. To support the added capacity to the current emergency power system in the hospital, a new geneartor plant will include 750 kW generators and a 5000 amp paralleling switchgear. A new 3000 kVA substation was added as well to support the additions to the hospital. Most lighting was 277V, since the majority of the existing hospital was already 277V.

Mechanical:
     The North Addition is fed by two new air handling units and one existing. One of the new AHU's is an interior custom modular design that serves all critical (patient) areas. The second new AHU serves the lobby and office spaces. The distribution system is a VAV system with variable frequency drives. The system utilizes medium pressure ductwork feeding VAV boxes with reheat coils. A new hot water heating plant was installed on the 2nd floor penthouse. It included the installation of two new steam to hot water converters with variable flow capabilities. In addition, new chilled water mains were ran from the central plant to the 2nd floor penthouse. The multi-level atrium/concourse was fitted out with a state-of-the-art smoke control system for fire protection.

Structural:
     The addition will consist of concrete slab on grade supported by a steel skeleton system on concrete footers. The footers are a minimum of 2.5' below grade. The concourse roof typically consists of a W10x30 beam at a 28' span supported by a W18x76 girder at a 26' span supported by "W" columns. The tower section is typically a 5 1/2" concrete slab on 2" deep steel decking. The decking is supported by W18x55 beams at a 29' span on W18x71 girders at a 21' span supported by "W" columns. The roof consists of a 1 1/2" galvanized 18 gage roof decking. All decking is welded to structural steel for lateral stability.

Fire Protection:
     The North Addition renovation is designed to the 2000 NFPA Life Safety Code. The ground and first floor sprinkler systems were reconfigured and tied into existing 4” sprinkler pipe main. The tower portion of the renovation had a new 4” standpipe installed with each floor of the tower having a dedicated zone valve. A dry pipe was installed for the canopy protection. Current fire department connections were relocated to accommodate the addition.

Transportation:
     There are two elevators and one set of emergency stairs installed in the new addition. The elevators aand set of stairs are located in the main tower and can be accessed by all four floors. Access to the elevator banks are straight off the main lobby and off of each floor's lobby. They are fed by a dedicated 480V 3-phase, 3-wire 225A panel with its own automatic transfer switch being fed by emergency mechanical branch power. The elevators are cable driven and equipment for the elevator bank is located on the roof of the new tower. In addition, the elevators are tied into the hospital security system and can be controlled remotely incase of an emergency.

Telecommunications/Security:
     In any hospital, security and communications are of utmost concern. Data, as well as voice systems, are imperative to maintaining proper operation of a hospital. Depending on the particular function of the space, most rooms have data lines feeding medical equipment which needs to send and receive information from central computers. Nurses and doctors can monitor vital signs and ensure patient health through these integrated data lines through the patieni care areas.
     For the new natal care ward, a state-of-the-art Infant Abduction Alarm System was installed. This system is very similar to a patient wandering system which attaches a band to the infant's leg that will set off alarms in the corridors and exit stairwells that alert nurses that a baby has left the ward unauthorized. This system is also ran to the main security system with the capability of locking all exit paths and halting elevator operation until the infant is accounted for.
     Since this is an addition to the hospital, all the above systems had to be integrated into the current security and communication systems already present in the existing hospital. This further challenged the design and installation of the systems and called for extra care in ensuring system reliability after the new addition was completed.