Modular, Precast Gain Popularity
- By Ellen Kollie
- February 1st, 2010
“The only thing to fear is fear itself,” said Franklin D. Roosevelt, in his first inaugural address in March 1933, which outlined how he planned to govern a nation mired in a deep depression. Seventy-seven years later, the country is again mired in economic woes, making it challenging for school administrators to provide much-needed classroom space for replacement and new construction projects.
Nontraditional construction methods are helping to provide that space, in part because they can offer financial savings over traditional construction methods. Nontraditional construction methods include — but are not limited to — SIP, tilt-up, ICF, modular and precast. For simplicity, this article focuses on modular and precast, showing the many benefits that are allowing these methods to gain popularity in the K-12 market.
In modular construction, individual modules are 60-percent to 100-percent factory built, then transported to and finished at the construction site. The industry’s leading organization is Charlottesville, Va.-based Modular Building Institute (MBI)
. The organization represents companies — by providing services and promoting professionalism — involved in the manufacture and distribution of commercial factory-built structures.
Industry experts note a number of reasons why modular construction is growing in the school market.
1. Off-site Construction
“When it comes to modular construction,” says Joseph C. Lopardo, vice president of Modular Buildings for Baltimore-based Williams Scotsman, which manages and develops large permanent modular construction projects from concept to completion, “there’s no site disruption. The main reason folks are coming to us today is because you don’t have truckloads of wood and brick delivered to the site because construction is being done in a controlled environment.”
“Having hundreds of students in the middle of a construction site is not the best scenario,” adds Tom Hardiman, MBI’s executive director. “There’s the possibility for theft, and of students being curious, going onto the construction site and being hurt. The controlled, off-site setting with delivery of the product makes modular construction more appealing to school officials. It’s a safer process.”
2. Time Savings
Time savings is another benefit. “In some cases, modular construction is 50 percent faster than conventional construction,” says Hardiman. “That’s because we are building the facility offsite while you’re simultaneously doing the site work.”
“And you’re not losing construction days from poor weather, like wind and rain,” adds Lopardo.
Modular construction also contributes to sustainability. It produces less waste than traditional construction because leftover product is used in successive projects, rather than being driven to the landfill. “In fact,” Hardiman points out, “only one-tenth of modular construction waste goes to the landfill.”
Further, at the end of a modular facility’s useful life, numerous components — if not the entire facility — can be recycled. “There’s no other building type that you can do that with,” says Hardiman. “When looking at lifecycle costs, the big picture is from cradle to grave. At the grave part, modular says, ‘I have an advantage here in that my parts are reusable.’”
4. Project Phasing
Many school districts cannot get the approval and funding necessary for a five- to seven-year plan. Instead, they have to look at the short term. Modular construction is an excellent option for short-term planning in that it allows for project phasing, providing the ability to easily add on as many units as necessary or change floor plans as growth occurs and funding becomes available.
5. Design Options
Finally, modular construction offers limitless design options. “Folks used to think modular construction was simplistic — a vanilla box,” says Lopardo. “Now that the design community has become more accepting of modular construction, we are able to show them our capabilities.” For example, instead of sending a school to the site, 90 percent complete, it can be sent 70 percent complete, with specialized roofs or atriums being added on site.
In precast construction, concrete is cast in a mold and cured in a controlled environment, then transported to the construction site and lifted into place. The industry’s leading organization is Chicago-based Precast/Prestressed Concrete Institute (PCI)
. The organization is dedicated to fostering greater understanding and use of precast and prestressed concrete, most notably through the development of standards and methods for designing, fabricating and constructing precast concrete structures.
According to industry experts, there are a handful of reasons why precast construction has been gaining popularity in the school market.
1. Time Savings
One of the primary benefits to using precast as an alternative construction method is that it shortens the overall construction time, and for school districts needing new facilities ready to go at the beginning of the school year, this is a huge advantage. Construction time is shortened because site work is being done while the product is being made in the factory.
“It would be fair to say that precast shortens construction time by 30 percent as compared to traditional construction methods,” says Carl Clary, technical sales consultant for Spartanburg, S.C.-based Tindall Corp., which designs, manufactures and erects total precast systems. “Other trades are able to get inside and start the finish work so much more quickly. It’s a trickle effect from the top down.”
2. Cost Savings
Cost savings is another primary benefit to using precast construction. “Precast is not the best solution for every school,” notes Clary. “However, there are certain criteria where it provides a financial benefit to the building program, if the school district chooses to go that way. For instance, precast is well suited to multilevel construction.”
Similarly, precast wall systems are vapor tight, thus eliminating or at least substantially reducing water issues throughout the facility’s years of service. And, if you use brick veneer on the exterior, there are no joints between the bricks, so it never needs tuckpointing. These examples speak to lower maintenance and lifecycle costs.
Precast also provides natural energy savings. The concrete walls, complete with uninterrupted insulation barriers, absorb and hold radiant heat from the sun, thus keeping the facility at a more constant temperature and reducing energy costs through time.
“Saving time and money is critical, but it doesn’t outweigh the importance of building an aesthetically pleasing school,” says Clary. “Fortunately, precast construction offers both beauty and design flexibility.
“We’re taking what’s been going on in the commercial market, architecturally enhancing it and taking to the school market,” Clary continues. “There has been tremendous development in the architectural finishes we can offer, so there are numerous ways to personalize façades and make them look as though they were constructed using traditional methods, but providing precast’s quality.”
Sustainability is yet another benefit precast offers. “Most school districts have some sort of requirement for sustainability today,” says Brian D. Miller, P.E., LEED AP, managing director of Business Development for PCI. “And LEED is the most common grading system available. Precast can help administrators meet LEED goals, especially if the precaster and designer get together early in the design process to optimize the design.”
“I think durability is a benefit not to be overlooked when it comes to precast benefits,” says Miller. “Precast lasts for a long period of time and is durable against Mother Nature. It doesn’t burn. It’s good against storm impacts like flying debris and water. In fact, water does not degrade concrete, it makes it stronger.”
K-12 administrators can choose modular and precast construction with no fear, knowing that both of these nontraditional construction methods can be used to create single classrooms or complete campuses, providing the same quality and materials, and meeting the same building codes, as traditional stick-built facilities.