When it comes to putting a building together, there has always been the tried and true styles that have transcended time. Over the years, the construction industry has tried to adopt many different building techniques in an attempt to efficiently speed up the overall process, while still successfully navigating through the complicated operation. Some of the advancements come in the form of new products, with improvements such as tools to save time during installation.
Other major innovations come in the form of offsite construction (prefab), combined with computer technology that adds organization and control to the whole concept. The prefab method has made several bold attempts to grab a foot hold in this industry for decades. It has demonstrated the potential to add significant value, but doing it consistently and on a large scale is quite a challenge.
With the advancements in tooling and technology, and increased awareness for personal safety protocols, there seems now more than ever to be a greater motivation to move into prefab or modular construction, for the framing side of the construction industry. The ability to manufacture buildings in a controlled work space not only increases consistency in quality control but also makes for scheduling to be much more predictable. The integration of modern planning, along with improved technology such as building information modeling and other mechanical integration programs, have helped create a more efficient and often much more cost-effective model. Within the walls of these prefab facilities there are significant advantages that come inherently with this mode of construction. Examples include waste management and material control, the ability to more effectively control potential personal injury to employees, material organization/usage and finally, overall control of job schedule.
Responsible waste management and recycling have become an integral part of all current and future projects nationwide. There is a great deal of planning and forethought that must go into a project to make sure that throughout the entire process waste is minimized, runoff and water pollution are controlled, and all jobsite delivered materials are on-site only when needed, due to limited space. While this process might be quite difficult in the field during normal construction operations, within the walls of the manufacturing facilities there is a more structured environment where managing materials more efficiently will ultimately create less waste.
When it comes to prefabrication, there is no “one size fits all.” Many companies in the industry have adapted, changed, or modified this style of building to make it their own. Introduction of innovative materials and processes have given new opportunities to the prefab process. This writer has personally witnessed multiple approaches over last decade.
Panelization and CFS
Wall panelization using wood has been active and stable during the past 10 to 20 years, and while CFS load-bearing structures are relatively new, their frequency and size seem to be increasing each year nationwide. There also has been expanded large scale structural testing as demonstrated at the world’s largest exterior shake table at UCSD engineering laboratory. (Video of recent shake table test performed on the first six-story CFS building is available upon request.)
With the advantage of providing the designers with a noncombustible, as well as lifetime structural performance, CFS structures have utilized automated welding of track and studs, incorporating the high strength steel backed composite shear panel system have demonstrated that there are more efficient and cost effective ways to put a wall and building system together other than the commonly used wood studs and plywood panels. These CFS panels can be transported long distances while resisting both movement and damage, reaching the destination ready to be craned immediately into place.
This style of panelizing positively impacts the efficiency in the framing process greatly, compared to conventional stick framing technique. Industry experts calculate that when framing with CFS, a typical stud wall average framing time on site is roughly ten lineal feet of wall per man, per hour. Using panelization techniques that yield, increases that framing time to approximately 25 lineal feet per man, per hour. This enhanced labor formula also needs to take into account the reduction of additional costs due to layout and framing errors, field changes from plan errors and omissions, and most importantly reducing those undesirable change orders. This is the result of the plans being reviewed and vetted months before the walls are actually built and put into place.
On many large projects, they can panelize the floors systems for these jobs as well, from joist and rim, all the way to the floor sheathing. This will reduce overall job costs by reducing the total installation time on your construction schedule. These floor and roof panels can be craned into place just like the wall panels. Ultimately, these methods and procedures increase profits.
Prefab or Modular System?
Now there are several companies providing a more complete product approach. Modular buildings constructed of CFS non-combustible materials that are coming to the marketplace more frequently, create a finished POD of habitable space with little assembly required at the end destination. I have recently witnessed modular construction manufacturing companies produce these completed PODs built in factories in Texas and Tennessee and shipped nationwide. These PODs are transported intact and wrapped ready to be stacked side by side or on top of one another locked and secured into place. The manufacturers have the capability of reaching heights of 30 stories or more.
More Opportunities for Prefab
The prefabricated systems don’t limit architectural designs unlike the modular systems. The PODs may limit the design somewhat due to the maximum finished dimension for transportation of the finished PODs. But these minor limitations only demonstrate the versatility of the systems that are available to choose from. As we look forward to the ever-changing building industry, and as we watch people continue to advance these technologies and products, they will create even more efficient and dynamic ways to construct your buildings and definitely create greater opportunities for prefabrication. When it comes to advancing technology, it happens so fast. Don’t miss your opportunity to investigate how these systems and prefabrication contractors might help you with your next project.