By Brett Seeney, Cardiff, UK, +44(0) 2920 827069, seeneyb@pbworld.com

When the UK government announced an unprecedented capital works expenditure for the National Health Service (NHS) to be delivered within five years, prefabrication, or off-site construction (OSC), became the focus of much debate within the industry. The healthcare community had previously seen OSC as appropriate for temporary accommodations or administration facilities. These buildings were considered functional but lacking the “wow” factor required of public buildings. Yet, NHS Estates has begun to look favourably upon OSC as being the only way of achieving its new build targets within the given time frame.

The case for OSC appears on face value to be compelling. A look at the literature from any of the OSC providers indicates the desirability for the approach as it can provide speed of construction, high quality design, cost effectiveness, and energy efficient and sustainable construction. There are now many examples of OSC facilities operating within the UK healthcare service, so evidence for adopting this construction method need no longer be anecdotal.

Two buildings are used in this article as a comparator of OSC and traditional construction considering the four benefits listed above, with cost effectiveness being discussed as part of each of the three other benefits. They are:

• Traditional construction. A traditional brick and block structure unit for the elderlymentally infirmed.
• OSC. A pre-engineered modular orthopaedic treatment centre structure. The client procured this project via ProCure 21, a partnering initiative devised to deliver the ambitious build programme through twelve pre-selected organisations. PB provides the engineering and architectural design input to one of the partnering organisations.

Both buildings were procured as new build and both were handed over for occupation at much the same time. In addition to its responsibilities mentioned above, PB provided the mechanical and electrical (M&E() engineering design for both projects.

Benefit #1: Speed of Construction

The comparator, which shows that the OSC approach delivered a 30 percent reduction in the build period (Table 1), would appear to concur that OSC provides the building faster. This approach reduced the design time as well, realising a 57 percent reduction in overall project time. The faster cycle allows the client to realise an income stream sooner, so the additional capital cost of OSC, which is typically in the region of 10 percent, will be offset.

Table 1: Data for Two Buildings Note 1: The design period is that from the time the team is commissioned. Note 2: The build period is that from construction start to handover. Note 3: The total period is that from appointment team to handover and includes approvals and other miscellaneous events.

Figure 1a: Construction of pre-fabricated (OSC) building modules.

Figure 1b: Delivery of pre-fabricated (OSC) building modules.

Whilst it may seem to be clear that improved speed of construction is realised through OSC, it is important that we examine this claim more carefully. Much of the outside evidence for OSC is based upon simpler buildings than healthcare facilities. These buildings have a low M&E engineering input whereas within healthcare buildings these elements comprise, by cost, 40 percent to 50 percent of the capital budget. If we add information technology and patient information systems, the building services share of the cost can rise to 60 percent and more.

The complex engineering services to be provided within a healthcare facility can become subject to a lowest cost design and build approach under OSC. This in itself does not pose a problem if the client requires the standard product, as with a temporary facility, but most often they do not, preferring a custom design to suit their operational needs as is discussed below.

Benefit #2: High Quality Design

The figures in the table indicate that more time is spent on designing traditional projects than on designing the OSC alternative—a reduction of 70 percent. Although some of this reduction is undoubtedly due to the ProCure 21 approach of partnering and supply chain involvement, there are aspects that can be attributed to the fact that OSC provides a standard repeatable module. The engineering design can follow this pattern and also provide repeatable detail. It is also of benefit in that the structural elements are predesigned to a standard. There is, therefore, no delay in providing building details for the M&E engineering designer.

It is also clear, however, that the M&E engineering services are being fitted into a pre-established building detail. This may result in a compromise over standards and quality that are avoided by the multi-disciplined approach that PB normally provides its clients.

It is generally accepted that the closer the designer is to the client the more readily high quality design is achieved. Much design time is spent in understanding the client’s unique drivers for the project. With medical facilities, clinical need often has a local and historical flavour, with each Trust preferring its buildings to function in a particular way. It is no surprise, therefore, that many OSC providers limit their pre-engineered elements to the structure and shell, and produce their M&E engineering services using a more traditional process.

Another point is that in many respects, OSC is a production line. Once the button is pressed, a building will be constructed very quickly. Changes can be difficult and costly, so everything must be specified and agreed to before production starts. This is often impractical.

The OSC literature claims that anything is possible. If anything was truly possible, why do we see only boxes with rectangular windows and a metal clad or painted render exterior finish? It would appear that with OSC, unlike the motor industry, the client devises the options, and these extras add to the cost and delay the delivery. Whilst it can be considered that OSC is bringing commercial aspects to bear on the healthcare market, departures from trusted guidance can leave the client feeling short-changed and accepting of second best.

Good design has been at the forefront of thinking behind building procurement within the NHS. In 1994 NHS Estates published the document “Better by Design — Pursuit of Excellence in Healthcare Buildings.” The document laid down the values to be expressed in good design and stated, “An attractive hospital need not cost more to build. If quality is seen as integral to the design and construction process, the probability of procuring fine, economical buildings which are flexible and tailored to the needs of present and future users is increased.”

Quality healthcare buildings enhance the patient experience and aid recovery. Does a rectilinear building filled with box type rooms achieve this? Are these lines of a rectilinear building with punched out rectangular windows what we, the consumers, want from NHS? Are we happy with a system that only considers the clinical function taking place within the building?

Benefit #3: Energy Efficient and Sustainable Construction¹

Economic Impacts. The two major costs incurred in the healthcare sector are salaries and pharmaceuticals. If you approach the healthcare client with an argument to save 10 percent on the energy bill, you should not be surprised when met with relative disinterest. If, on the other hand, you present an argument that says the patient can be discharged sooner, needs less analgesia whilst in care and, incidentally, saves 10 percent on the energy bill, then everyone in the room will be sitting up and taking notice. Consider a building that promotes buoyancy driven natural ventilation and day lighting throughout, and reduces the staff’s daily travel distances around the department. The building does not have harsh rectilinear features, and better responds to patients’ needs for tranquil spaces, thus reducing the need for analgesia and promoting faster recovery times. It is not doubted that such a building can be designed and built, but can it be delivered through a process geared to mass production?

Societal Impacts. Construction is a labour intensive activity. A major building project will engage many small tradespeople and unskilled workers from the immediate area, ranging from bricklayers and carpenters through to labourers and cleaners, including the person with the canteen. With OSC, many of these employment opportunities are lost to the local area.

Environmental Impacts. Clearly the location of the OSC production plant relative to its suppliers and to the building site is critical if we wish to minimise the environmental impacts caused by transportation. In the case study, the OSC manufacturing facility was based in Germany, more than 1400 km (900 miles) from the site. The building was transported by road and sea to the UK. Forty-five lorries each carried a 15-m by 5-m (50-foot by 16-foot) load for that distance, burning around 5000 gallons of fossil fuel (Figure 1).

In the case study, 50 percent of the services installation was to be fixed at works in Germany by a UK-based contractor, who shipped materials and equipment from the UK. This included the shipment of some items that were originally manufactured in Germany, a total journey of 4200 km (2700 miles), using about 350 gallons of fuel, for these components.

Conclusion

Clearly, OSC has the potential to realise faster overall construction times. But this should not be read as a de facto statement. Any deviations from the standard will impact upon both cost and time to deliver, so it is imperative that all design decisions are taken in advance of the OSC production.

Construction in factory conditions leads to better quality at key points such as junctions and openings. Whilst this method may produce lower energy costs after the building is opened, this is not generally a key driver for the healthcare sector. Cost effectiveness may be better served by the construction of high quality buildings that reflect the research undertaken into how environment affects recovery. This may mean organic buildings and properly engineered and controlled natural ventilation.

What we as construction professionals must do is to ensure that our clients are able to make informed decisions. Our problem with OSC is that there is little impartial information available, and much of what there is may not be strictly relevant to healthcare or is embryonic. What is required is a simple rubric that can be applied to each project. This may start with the premise that OSC is the standard and then work through the particulars of the site, client drivers, etc. to arrive at a decision to adopt or abandon it.