Modular Building Construction: What You Need to Know
For more than a year, large portions of the construction industry have struggled to keep up with the complications of COVID, an onslaught of natural disasters like hurricanes, earthquakes, and tornadoes, and an ever-growing shortage of skilled workers to help repair and rebuild. To contend with these challenges, designers and engineers are looking to modular construction. Modular construction is a standard go-to for rapid disaster relief and short-term building efforts, but it has evolved into a highly flexible, scalable, and durable solution that offers real long-term value.
What is Modular Building Construction?
Modular building construction is a method of prefabrication consisting of repeated sections called modules. Individual modules are fabricated off-site and delivered to the intended location for installation and construction. Cranes are often necessary to place prefabricated units. Modules may be arranged side-by-side, end-to-end, or stacked, allowing for a variety of configurations. After placement, the modules are joined by inter-module connections or interconnections. The inter-connections tie individual models together to form the complete building structure.
Modular building construction is the subject of ongoing research and development worldwide as the technology enables increasingly taller structures. As we touched on earlier, various industries are adopting modern modular construction for short- and long-term facilities and permanent installations, including construction camps, schools and classrooms, residential homes, and military buildings. Modular buildings are ideal in remote and rural areas where conventional construction is inefficient or even impossible. The portability, flexibility, and speed of construction of many modular buildings make them popular for staff and attendees at all manner of events locations where appropriate facilities don’t exist or cannot support capacity demands.
Modular homes and commercial buildings are sturdier than traditional structures thanks to replacing nails with screws, adding glue to joints, and using 8-10% more lumber than conventional methods. According to a FEMA study on the destruction wrought by Hurricane Andrew in Dade County, FL, modular and masonry homes fared best compared to other construction types. Modern modular dwellings are built to local, state, or council code, meaning different facilities may have differing construction standards depending on the final destination of the modules.
The essential zones manufacturers must consider are local wind, heat, and snow loads. Structures built for final assembly in a hurricane-, earthquake-, or flood-prone zone, for example, may include additional bracing to meet local building codes. Steel is commonly used as both a building material and reinforcement in modular buildings.
What Are the Key Benefits of Modular Building Construction?
Saves Time: Modular building construction allows a significant portion of work to take place off-site while on-site and foundational work is performed simultaneously. Modules arrive on-site outfitted with features like flooring, cabinets, counters, plumbing, electrical fixtures, and appliances ready to go. Throughout an entire project, modular construction can potentially save up to 50% of overall scheduling time compared to a traditional site-built structure.
Reduces Labor and Logistics Costs: The COVID pandemic has and continues to cause massive challenges to the availability of skilled labor in most places. Workers are costly and sometimes completely unavailable for the demands of a given timeframe or budget. Modular building allows manufacturers to take advantage of skilled workers in other fixed locations with better safety and quality control than the final construction site. Modular construction plants can be strategically placed where the workforce is located to build the strongest teams and take advantage of critical logistics connections and raw materials.
Safer for Workers and Tradespeople: Modular building construction is safer for workers due to the safety standards within manufacturing plants. Workers also have immediate access to safety gear such as helmets and harnesses and aid stations for eye flushing or other minor injuries. These facilities are also climate-controlled, reducing the risks associated with slippery and excessively hot or cold conditions.
Improved Price Predictability: Since most of the design and planning process is accomplished at the beginning of a modular building’s design-build process, builders often find a significant improvement in price predictability. Compared to other commercial construction methods, modular construction enables builders to stay extremely close to the initial estimate.
What Are the Biggest Challenges of Modular Building Construction?
The biggest challenges of modular building construction consist of logistics, hook-up, and sequencing.
Logistics challenges include defining alternative fabrication centers in case of an emergency, survey site constraints, site access, securing safe transport routes, transportation limitations, and resources for material loading and unloading.
Hook-up and commissioning is a critical phase in developing modular buildings, making good planning and control essential. The Planning and Control of Offshore Hook-up and Commissioning describes the challenges of offshore hook-up and commissioning with the following:
The availability of beds offshore strictly limits the size of the strictly limits the size of workforce which can be employed on hook-up work and, therefore, imposes and major constraint on the schedule. Hotel- ships can be used to supplement the number of permanent platform beds but will substantially increase the manpower cost.
On top of bed limitations, safety regulations and operating practices restrict manning levels. The early commissioning of safety systems and equipment is critical in influencing how quickly labor can be mobilized.
Sequencing and proper work scheduling can lead to shorter time allowances for large cranes and other equipment in the field. Proper construction sequencing minimizes the handling of equipment modules, increases cost efficiency, and improves safety.
What Does a Typical Modular Construction Process Look Like?
Design Approval Stage
The modular building process starts with the design phase. Architects and engineers create interior and exterior plans for approval by the property owner and local or third-party associations for all necessary building permit applications. Modular buildings must comply with the local codes and zoning of the final building location, not the location of the module construction!
Modular Component Construction Stage
Modular components are constructed in a controlled off-site facility while site excavation and grading occur on-site. As factory work can compose up to 90% of the work performed on the project, the labor force can include:
- Drywall finishers
- HVAC workers
- Flooring finishers
Third-party inspectors and other building code officials visit the factory at various stages. Once the modules are completed, they’re prepared for transportation to the site.
Modular buildings and components are often integrated into the chassis of trucks for transportation to the project site. The resiliency required by preconstructed modules to withstand the transportation process dramatically contributes to the overall exceptional strength of the final building.
Transportation of modules considers factors like costs and methods of transport, travel distance, and weight. Maximum desirable distances typically range between 250 to 400 miles. Any further and the costs and transportation difficulties can increase substantially.
Final Module Erection
The modules are stacked by crane or rolled onto the foundation at the final job site. Modules are bolted together and sealed against weather, utilities are hooked up, and exterior components are completed.
Trust APEX for Your Modular Building Construction Needs
APEX is a leader in modern modular construction and modular piping services, straight out of our old-world shops. Every component of every project we participate in is fabricated to specification and transferred directly to your site exactly when it needs to be there. Successful, long-lasting modular construction projects demand skilled engineers, mechanics, electricians, plumbers, and more. That’s exactly what our integrated team delivers, with superior capability, experience, and technologies to provide the best results possible.