Because they are reusable and easy to assemble using clamps and pins, modular systems offer significantly faster cycle times than traditional, stick-built formwork. CII researchers also found that once modular systems are assembled, they also offer a higher-quality finished concrete and are generally safer for crews due to fewer loose parts and pieces on the jobsite.
However, modular systems take time to erect, require extensive lay-down space and are crane hogs.
Stick-built systems, on the other hand, have the advantage when a schedule demands quick setup and when real estate is limited on the jobsite. Traditional systems also are more flexible because crews can modify them easily in the field with a quick saw cut.
Who was the winner? It depends. CII’s research team found that on a hypothetical, 60-story office tower built in Houston and Chicago, a modular system’s edge depends solely on the local labor cost.
In Houston, where labor rates are generally lower than the rest of the country, the project would benefit from modular formwork starting from floors eight through 10.
However, if the same office building were being built in Chicago, where labor generally costs more, the modular system would have a distinct advantage from floors four and five onward.
“This doesn’t necessarily have to apply just to an office building, it applies to anything that has a repetitive nature to it,” MacNeel noted.