In recent decades, the growth of pre-engineered metal buildings (PEMBs) has outpaced that of traditional structural steel buildings, making them the default solution in the global metal building construction market.
PEMB details
PEMBs are defined as structural steel buildings pre-engineered and prefabricated off-site, then delivered as one complete package and assembled at their final location. According to the Metal Building Manufacturers Association (MBMA), the attributes of this type of building include:
Single source supply: Building design, fabrication, delivery, and construction are all managed through one single source.
Efficient materials and construction: Each building is constructed quickly, saves energy, lasts long, and is environmentally friendly, with virtually no waste in the manufacturing process–and materials are fully recyclable.
Flexible design: Flexible interior and exterior elements allow numerous design alternatives. Exteriors can be clad with steel siding, wood, glass, aluminum, masonry, or concrete.
A critical review of the unique benefits of PEMBs compared to other forms of building sheds light on the product category’s unmatched growth. The aspects to review include design, materials, installation,
and protection.
Benefit #1 – Design flexibility brings value
Value engineering: In recent years, PEMBs have shifted from using hot-rolled section profiles (straight sections) for primary and secondary structures to built-up sections (tapered as needed) combined with light gauge materials. This solution offers significant economic advantages, saving at least 25 percent in material usage compared to traditional designs. These engineering advancements allow builders to reap the unique benefits of each manufacturing process for different structural elements. Not all manufacturers have the capabilities to produce this variety of steel forms, but those who do can offer steel options that maximize performance at the lowest possible cost.
Expanded uses: PEMB structures were traditionally used in industrial applications, including warehousing, car parks, storage facilities, agricultural operations, and gas stations. While MBMA estimates that more than 60 percent of PEMBs still fall into an industrial or commercial category, PEMB usage in additional categories is growing, including retail, offices, community structures, recreational buildings, and religious, educational, and healthcare facilities. This expanded use is due to nearly endless design flexibility and enhancements in engineering and architecture.
Benefit #2 – Common materials for faster delivery
Built-up section framing: As mentioned previously, PEMBs enable custom engineering and manufacturing of the exact frame elements needed rather than relying on standard parts and pieces. Utilizing standard columns and beams often results in an over-engineered structure with more steel than is necessary for specific structural areas. Alternately, built-up frames used in PEMB enable the design and fabrication of the exact thickness needed for nearly all the design capacity, reducing costs while delivering the same performance required.
Readily available raw materials: PEMBs offer faster delivery due to the availability of sheet plates and sheet coils. This advantage allows steel fabricators to stock average variable sizes of sheet plates and several material thicknesses, which form the basis of the structural design. This contrasts with the longer lead times for procuring hot-rolled section profiles in conventional structures.
Benefit #3 – Easier installation results in fewer errors and greater cost savings
Frame uniformity: The value design engineering concept ensures uniformity in repeated frames, leading to quicker installation times and more economical solutions at project sites. Modular designs facilitate organized and phased installation processes.
Pre-cut components: Because PEMBs are prefabricated offsite, little to no on-site cutting or welding should be required for building installation. The MBMA estimates that utilizing PEMBs reduces portions of the installation schedule by 30 to 50 percent, accelerating construction for faster completion.
Fewer errors: The single-source supplier model for PEMBs results in fewer errors in the final delivered materials because one company designs and manufactures all components to fit together, delivering materials right the first time.
Labor savings: PEMBs’ installation benefits result in faster and easier installation structures with less waste and rework so that builders can expect lower labor costs for the project compared to other structure types. This is increasingly important as construction analysts report that at least 500,000 skilled construction workers are needed to meet current industry demands. Further, construction labor costs increased more than 4 percent last year alone, according to Mortenson’s Construction Cost Index Report.
Benefit #4 – Design contractors can depend on
The strength of metal: Compared to traditional materials such as wood, PEMBs’ steel structure offers many advantages, including longer average life, better performance in extreme weather conditions, and resistance to rot, fire, corrosion, and pests. Some elements of this enhanced durability may qualify the structures for lower insurance premiums for impact resistance, fire resistance, or energy efficiency.
Welded connections: Using built-up sections reduces overall building material costs and can lead to greater strength and performance. Built-up sections allow for welded connections during fabrication, shifting the focus to mainly bolted connections. Shop-welded connections provide greater structural integrity and better resistance to buckling for taller columns and reliable surface treatment for the members.
Seismic resistance: Some research also suggests PEMBs are more seismic-resistant than wood structures due to their improved strength-to-weight ratios. PEMBs are constructed from lightweight yet strong steel, so they appear to be less susceptible to inertia when struck by seismic forces.
Warranties: PEMBs can offer end users and investors greater peace of mind because they typically carry better material warranties when purchased from a trusted major manufacturer. Buying all building components as a single package also ensures everything is included under one manufacturer’s warranty terms rather than separate suppliers.
The advantages of PEMBs over traditional materials like wood are clear. Even when compared with other metal building forms, PEMBs offer a unique set of advantages that can benefit a wide range of structure types, resulting in greater performance and lower material and installation costs. This solidifies PEMBs as an option that builders and investors cannot afford to ignore.
Ahmed S. Abdelaal is the vice president of engineering and operations at Central States Building Works. Ahmed brings almost three decades of industry experience working for some of the largest pre-engineered metal building (PEMB) companies in the United States and internationally. He came to the Central States after spending 11 years of his career at American Buildings Company (now Nucor) and Butler Manufacturing Company (now BlueScope Steel), where he held leadership positions in engineering and project management. For the last 12 years, Ahmed has served global companies by building out factories and technical capabilities in executive operations roles.
