How Are Modular Buildings Assembled?
What do you know about the ins and outs of the modular building construction process? Modular buildings are very different from their traditionally built counterparts because they’re fabricated off-site via an assembly line process. Read on to learn everything you need to know about modular construction techniques, design, engineering, and final installation.
One of the main benefits of modular construction is its accelerated timeline as opposed to traditional building projects. Off-site fabrication and on-site preparation can be completed at the same time, making the modular construction process 30-50% faster.
Modular building assembly also takes place in climate-controlled factories, helping you avoid weather-related delays that can sometimes impact traditional construction. Each module is up to 90% complete when delivered to your job site and can be placed on the foundation and seamed together quickly and efficiently.
Modular buildings are fabricated using an assembly line system and undergo inspection and testing every step of the way. These modular factories also maximize employee efficiency and productivity while ensuring the highest levels of quality and safety.
Completed modular buildings must satisfy the same building codes and standards as site-built structures. And modular building construction materials are just as durable and high-quality as those used in traditional construction. In fact, modular buildings are generally stronger than site-built structures because they must withstand the rigors of transportation and craning onto foundations.
If sustainability and a minimized environmental impact is important to you, modular is a much better option than on-site construction. A modular building factory is far safer than a construction site, and there’s no material waste because everything is stored indoors. Plus, manufacturers can easily save and reuse scrap materials for their next project.
Modular buildings can also be designed and built to meet the highest Leadership in Energy & Environmental Design (LEED) standards. This Canada Green Building Council program certifies construction projects with a rating system based on eco-friendly building strategies and processes. Ultimately, modular building design and construction embody adaptable reuse and the green lifecycle because these structures can be disassembled, relocated, and refurbished multiple times.
What to Know About Modular Building Design & Engineering
Some companies choose to work with an architect to design and engineer their modular structure. However, an increasing number of businesses are opting for an integrated modular building system, which involves working with the manufacturer on a complete design-build project. These fabricators are referred to as design-builders or design-build contractors.
Developing preliminary (or fully engineered) designs for your custom modular building allows you to create a structure that exceeds your needs. Many manufacturers (including BOXX Modular) already have floor plan libraries that are designed to meet the unique needs of businesses in a variety of industries.
The modular building construction process can be broken down into a distinct series of steps. We’ll take a closer look at each one in the following sections.
The first step of modular construction assembly is framing out each individual module. Most modules have a maximum size of 14’ wide by 76’ long due to over-the-road shipping restrictions.
Wood is the most commonly used framing material because it’s extremely easy to work with and source and is relatively affordable. Wooden frames also offer a reduced risk of electrical shock and low toxin levels. Additionally, wood is a sustainable and biodegradable modular building construction material.
You can also opt for a steel and concrete frame, which includes a steel and concrete floor deck and cold-formed steel wall panels. These frames can be either outrigger or perimeter:
- Outrigger frames have longitudinal rails with steel outriggers that extend from those rails to support the outside walls.
- Perimeter frames rest on perimeter foundation walls (or piers) to support the building from below.
Steel frames are made from up to 80% recycled materials and are often recyclable at the end of their useful life. They’re also fire-resistant, use fewer raw materials, offer larger beam span openings, and provide more consistency between pieces.
2. Flooring & Decking
Floor joists and decking are built at the same time as the framing. Once the frame is ready, the floor joists are affixed before the plywood decking is attached. The most common flooring materials are vinyl composite tiles (VCT), ceramic tiles, carpeting, and vinyl planks. At this point, the structure begins moving down the modular building production assembly line.
The walls of your modular building are constructed using traditional wooden studs and spaced according to wind load requirements. They’re built in a horizontal position before being lifted into place and attached to the flooring and frame. The most common wall materials are drywall and vinyl-covered gypsum (VCG), which involves less preparation work than drywall.
4. Interior Finishes
At this point of the modular construction assembly line, interior wall finishes, windows, insulation, electrical wiring, and plumbing are all installed. Any custom modular building components are also installed from outside of the module.
Next, the roof structure is attached to the modular building using an overhead crane. Roof decking is also installed and covered with an exterior waterproof surface. Due to Canada’s colder climate, most companies will choose a material that melts snow faster and absorbs heat.
6. Exterior Finishes
Once the roof is finished, ductwork and any additional electrical wiring are run. HVAC systems are also installed, along with the ceiling, flooring, doors, trim, and any exterior finishes. Popular exterior siding materials include:
- Composite exterior panels
- Modified wood
- Stone veneer
- Thin brick
- Ribbed steel
7. Shipping Preparation
When the modular building construction process is complete, the structure undergoes all of the inspections required to ensure compliance with applicable codes. Each module is then cleaned, weatherproofed, and moved to an outside staging area in preparation for delivery. Modules are placed in a predetermined order so they can be delivered and installed as quickly and efficiently as possible.
Modular Construction Assembly On-Site
Site preparation happens at the same time as the modular building construction process for maximum efficiency. On-site preparation begins with excavation and grading for foundations and their subsequent installation. There are two foundation types: on-grade and raised:
- On-grade foundations are created by pouring a foundation wall around the perimeter of the building. Each individual module is then set with a crane during final assembly. This foundation type is typically only used with permanent modular buildings.
- Raised foundations are concrete piers or blocks that individual modules are placed on top of. They typically don’t require a crane and are used for both permanent and temporary buildings.
Around the time the foundation is being installed, utilities, storm-water management systems, water and sewer systems, and site drainage are applied as necessary. Walls, ceilings, electrical, data, plumbing, and HVAC systems are connected at each mate line, which is where the individual modules meet. The units are then seamed, which involves the installation of exterior facades and weatherproofing materials at the mate lines, interior floors, and wall finishes.
Once the building installation is complete, the structure is connected with utilities, water and sewer lines, alarm systems, and data sources. Skirting is also placed around the bottom of temporary modular buildings to hide any space between the structure and the ground. BOXX Modular can also help you furnish your buildings, with furniture packages for offices, lunchrooms, and more.
Ready to solve your space needs?
Modular buildings are the way to go. Request a quote or contact us today to get the conversation started. We’d love to talk to you about how modular can meet — and exceed — your needs.