Today, Emergency Departments (EDs) are expanding in record numbers for a variety of reasons. In addition to rising volume in emergent care, patients also use EDs as walk-in clinics. The fact that EDs are often used as the front door, with a greater percentage of seriously ill patients (statistics show upwards of 50% are admitted based on our examination of hospital annual admissions reports), is driving changes in design configuration. In addition, the increased use of imaging equipment and the requisite power and area requirements affect space allocation. Whether to build new or to expand in place is often a thorny question. Is it less expensive to reconfigure? Is it more disruptive? Is there sufficient space and/or power capability in an existing facility to accommodate new modalities?

The following four steps can help an administrator decide whether expanding or building new is the most cost-efficient option for his facility's requirements. In the examples presented below, planners assessed two community hospitals—a large, Trauma Level I hospital and a smaller community medical center—and arrived at two different solutions.

Facility Assessment

An assessment is necessary to determine whether your facility is capable of a viable ED expansion that will be worth the return on investment, and if modifications over time have improved or limited your ability to provide quality patient care in a contemporary ED environment. Furthermore, new regulations like HIPAA might have rendered your care-delivery model obsolete regarding your current versus preferred patient intake processes.

This facility had outgrown the existing ED, and the tight city site required a street vacation (closure) and building expansion over the former road. The new facility was designed around new structural bay spacing for greater flexibility and to incorporate new technologies

In the master planning stage, a good design team will tour the entire facility to provide a complete assessment. Some facilities built more than 20 years ago may not even meet current infrastructure standards. Each area of the facility should be viewed and ranked as good, fair, or poor. It is important to analyze how existing space can be used, if it can be used at all. Planners should first attempt to reconfigure space by changing workflows, constructing or removing walls, or using noncritical, “soft” spaces.

For example, the ED in the large hospital was designed with two entrances, though only one was operational. The single entrance served walk-in patients and those brought in by ambulance. The assessment found that if the existing entry sequence could be reconfigured and segregated as originally planned, access to the interdepartmental imaging capabilities would be excellent (figure 1). Because patients were funneled into a tight entry and foot traffic was not moving well, planners decided the entry should be modified and the intake process streamlined. Using a plan to expand in place, the new design would add staging space and take advantage of the adjacencies that were afforded with the existing design (figure 2).

Similar analysis at the smaller medical center revealed the ED space was insufficient. Its open-bay design simply didn't allow for current quality and private medical treatment. Current planning for new EDs requires additional space for more seriously ill patients and their commensurate medical equipment (see sidebar), longer patient stays in the ED, and comfortable waiting space for friends and family. In a site where planners cannot find the needed space by borrowing from soft spaces, altering care methodologies, and changing patient flow, healthcare providers need to prepare for a complete replacement space.

The floor plan illustrates direct and simple flow of this Chicago community hospital ED. The design emphasizes optimal adjacencies, separation of inpatient/outpatient flow, and quicker throughput.

Capacity Analysis

Having key rooms to respond to current and anticipated volumes that correspond to patient acuity levels in your ED is paramount to a healthcare provider's success. Also important is the analysis of the emergency cases that are driving more complex diagnostics within the department, and whether delivering this care within the ED is feasible. Another critical success factor is verification that increasing capacity is consistent with your strategic plan, i.e., can you support more admissions in your current facility and is the payer mix workable.

A capacity analysis based on key-room need will drive the size of the facility whether it's expanded or built new. In addition, understanding the patient acuity levels will drive throughput. Based on the volume of emergency cases coming in, planners need to know if the current facility has enough key rooms to support that volume. Each room that handles a treatment modality, such as a cast room, trauma, cardiac, etc., should be assessed. (These rooms are not to be confused with support rooms—utility rooms, offices, break rooms, lounges—which are all ancillary spaces.) In the example of the smaller medical center mentioned above, acute emergency volume growth and walk-in clinic patients saw significant volume increases over the past decade, most with imaging needs.

In larger EDs, more space usually is available and can be reoriented and expanded to provide the additional room needed. If a capacity analysis shows that expanding makes more sense than building new, the ED can expand in place. The existing ED can be reconfigured while portions are built, and entry sequences can be changed until the project is complete.

Space Analysis Programming

Once the facility assessment and capacity analysis is complete, the next step is finite functional and space programming. This means all rooms are identified, operational delivery methods are clarified, and finally a “test to fit” analysis is exacted. In the replacement scheme, the most contemporary models can be created, limited only by site and building expansion limitations. New imaging modalities are incorporated into universally designed modules that can flex for future needs.

Renovation programming sometimes results into what planners call “backing in” to the program. Backing in is accomplished in two ways: (1) by using existing soft space to expand, such as space that was used for ancillary areas like lounge, lockers, etc., and (2) using separate treatment modalities like imaging rooms where equipment can easily be added while maintaining operations during construction and installation.

At this stage, adroit planning will include an assessment of the percentage of patients seeking services such as trauma, cardiac, walk-in, acute treatment, etc. Finite programming investigates what types of rooms are needed, and how quickly these patients can be cycled, with an ideal throughput of under one hour. If a patient is being admitted from the ED, he will usually remain there for two to four hours because of insurance requirements preadmission testing.

Many smaller facilities have elected to design universal rooms allowing for ultimate flexibility (figure 3). The rooms can be used for walk-ins, acute patients, and others. Trauma-level centers tend to have their EDs segmented into specific rooms—cardiac, trauma, and fast track.

New operating models also must be supported by a facility's culture. Does your facility treat all patients in rooms, or in an open-care setting with a “no wait” philosophy? Is there a viable decentralized imaging modality available separate from the general diagnostic area? Also, a trickle-down effect of a larger ED is the facility-wide impact of an increased need for beds and other ancillary services to accommodate the larger volumes anticipated. These and other cultural concerns should be taken into account.

Infrastructure Analysis

Infrastructure analysis is predominantly engineering-focused to ascertain several factors, such as whether floor-to-floor heights and column spacing are capable of serving the needs of the contemporary ED with imaging capabilities. The current information-systems backbone should meet the demands of new technologies, such as Web-based picture archiving and communication systems (PACS), and HVAC design must conform to ASHRAE 90A requirements for pre- and final filtration.

In best-case scenarios, the infrastructure analysis occurs simultaneously with the programming phase. The facility assessment tells you what the problems are with the current ED, while the infrastructure review tells you how exactly you're going to rectify it. The objective is to determine what types of support space should be included in the program and to determine the structure's ability to house heavy diagnostic equipment loads where identified.

Depending on when the original structure was built, new requirements for power and cooling loads and the quality of energy needed for sensitive scanning equipment may not be available from local power suppliers. Energy feeds will need to be updated and conditioned for power spikes. You may find that the local power supplier will need to upgrade its services to handle this increased load. When a total infrastructure upgrade is necessary, including new air-handling equipment, new emergency generator capacity, and medical-gas systems in all rooms, the final plan could require a significant upgrade to the central plant, adding unexpected and out-of-scope elements to a proposed project.


For the best planning, the ultimate goal is completing a thorough and comprehensive evaluation and assessment analysis before beginning design. New emergency designs need to be adaptable and able to accommodate the most advanced technology available with an eye toward the future. The triage function of the future will likely include a CT scan as part of the treatment protocol on all medical patients. Whether an ED can expand in place or new space must be found, the objective is quick and accurate diagnosis with throughput times that are better than current best practices.

Many smaller facilities have elected to design universal rooms allowing for ultimate flexibility with adaptability of patient acuity in mind.

Whether a particular ED opts for universal or specific-treatment rooms, it's critical to plan for flexibility down the road. Rooms and bays are expected to last 10 to 15 years, but an X-ray machine is obsolete in a much shorter time frame. Regardless of the use, an adequate-sized room must be specified, with heavy-duty power capabilities that allow for updated equipment every few years at least into the next decade. HD

Michael D. Doiel, AIA, is a Senior Vice-President with HDR, Inc. He specializes in healthcare facility planning and design and is based in HDR's Chicago office.