Promising Prefabrication
One of the most frustrating aspects of construction is the time it takes to complete a building. The parts and processes that comprise healthcare construction—buyout, subcontractor mobilization, manual labor with tools and machinery—are pretty much constants, which means there is very little opportunity to shorten the process. Without a significant way to shorten construction, costs will be fixed in a relative way. It could be argued that without innovation in the construction process, there is a ceiling on productivity increases over time. All things being equal (specifically, fixed costs like equipment and labor), construction costs would never go down—a depressing thought for administrators hoping to do more with less capital.
On the bright side, shortening the construction timeline is the ripest target for innovation. It has been a tough nut to crack so far, but it will happen. Prefabrication appears to offer the most promise since it seems to be the method that has received the most research and experimentation, especially in modular housing.
At the HEALTHCARE DESIGN.10 conference, I saw a presentation about a successful prefabrication effort on a healthcare project. The architect presenting, Tim Fishking from NBBJ, provided three main reasons, and two others, why the owner and team chose to pursue prefabrication:
1. Budget control — Prefab could reduce construction time and, therefore, overall project cost.
2. Schedule control — Sequencing was not a concern so more work could be done early.
3. Increased quality — Work done in a controlled "shop" environment, assembly-line style with no overhead work required.
4. Tight site — Sub and labor parking and staging areas were virtually non-existent.
5. Collaboration opportunities — The idea of working with the construction side from the beginning to solve problems.
The two ground rules for how to use prefab were: 1) function comes first, and 2) aesthetics cannot be compromised. Given those rules, five major parts of the job were targeted for prefabrication:
• Curtainwall — unitized; glazed in a conditioned environment; less site impact with crane and lifts; quicker installation.
• Temporary bridge — manufactured by airport tarmac manufacturer for $980,000 vs. $1.2M; assembled in three days, disassembled in one.
• Caregiver support space — modular office furniture used in corridor instead of permanent charting and nurse stations.
• MEP racks — unistrut seismic frame; units pre-connected; bulkheads with smoke seals bookend; "no fly zones" for maintenance.
• Patient room units — same-handed allow massive prefab; 178 units broken into casework, headwall, and toilet parts.
Overall, the presentation was very promising. The project was complex: a tower addition to an urban hospital while the entire area was to remain in use. In addition, it was in Ohio, so weather and seasonality were a concern. The patient room floor plan was repetitive, but did not lack on the design end; the facade had a nice, sweeping boomerang look to it, and the room footprint had some unusual angles. The project was definitely not the easiest to attempt something ambitious like prefabrication.
Unfortunately, the team does not have the final cost savings data in yet. However, the team projects savings in labor cost (20%), improved productivity (30%), worker safety (zero incidents), reduced waste (estimated 91,000 cubic yards versus a single dumpster), and expected measurable improvements on quality, flexibility / maintenance, and schedule are yet to be determined.
Other than the apparent successes above, I noted a few more takeaways. First, as the saying goes, if you cannot measure it, you will not be able to improve it; the more you keep track of, the more you can see how prefabrication can affect it. Second, the team took advantage of units of material as they were delivered to the site (as much as possible), including metal stud lengths and pipe runs, which also helped align to the structural grid.
Third, the team used mock-ups holistically for staff, owner, subcontractors, and regulatory agency review. The mock-ups allowed for both a “pencils down” and “no more changes” promise from both the designer and users. Fourth, production was videotaped for later quality reviews and to verify how some work was accomplished (for instance, location of blocking). Finally, there were some adds that must be considered. This particular design required plywood to give the units stability so they could be easily lifted into place when on site.
What impressed me the most about this approach was the quality of design and depth of prefabrication used. In his Lean talk at the conference, David Chambers discussed prefabrication on a different scale with CareCyte, a modular, miniature critical access hospital-type design for easy “deployment” on site. This is prefabrication on an entire building level.
There are still many places to learn from in prefabrication, specifically the military, which requires quick, efficient assembly, and European architects, who have been experimenting with it longer. If it can be fine-tuned, prefab offers the possibility of massive productivity gains and cost savings in our future healthcare projects.