Appropriate in Any Climate
- By Janet Wiens
- May 1st, 2011
From California to Maine and from Idaho to Florida the challenge for college and university facility professionals is the same: build cost effectively. Oh, and make it sustainable, and it must work within often tight schedules. The need to get the most for the money means that administrators are often choosing building options other than “traditional” construction, including the use of precast, modular, and insulated concrete forms for a project’s structure. The good news is that each of these three options will work well in all geographic areas of the country and in every climate. The task, as with every project, is to evaluate the benefits, costs, and required schedule while also making certain that architects, contractors, and suppliers experienced in the potential approach are close at hand.
Location and Accessibility
Jamie Farny, market manager, buildings, with the Portland Cement Association, says that site accessibility can make one choice preferable over another. “Many times the site will impact the selection of a building approach. It is important to consider location very carefully.”
Precast construction often requires the transportation of large panels to the project site, and delivering modular units can present the same challenge. Access roads must be large enough to accommodate the delivery of the panels or modular units. In addition, the site must have adequate area for the cranes that are necessary to lift the materials into place. Using ICF for a project can make the site and access issues less daunting. “You can’t move far along in a project without considering the project’s location within the campus community,” Farny says. “Accessibility and minimizing disruptions to vehicular and pedestrian traffic during construction are very important.”
For Farny, the geographic location of a project relates more to available suppliers than it does to climate. “Facility personnel must consider how far materials will have to be transported to the site, which is especially true when it comes to budget and sustainability considerations,” he says. “Longer transport distances increase costs and are also less desirable from an environmental perspective.”
Farny believes that geography and the associated climate may be more of a factor at certain times of the year. Construction during winter months in the northeast, as an example, may be easier on some days with modular construction versus ICF, though both are always viable options.
From Hot to Cold
The weather around Chicago fluctuates from well below zero during the winter into above 90°F in the summer. When officials at North Central College (NCC), Naperville, IL, evaluated building approaches for a new residence hall, they considered many factors, including the college’s location.
“Our temperatures vary greatly throughout the year,” says Michael Hudson, vice president for business operations at the College. “We selected precast construction based on aesthetics, price, the availability of experienced sources, schedule, and the benefits it offered.”
The project involved the construction of a new 265-bed dormitory that surrounds a 62,000-sq.-ft. field house. The $20M structure features precast dormitory walls, floors, and ceiling members. The enclosed field house has 50-ft.-tall precast sandwich panel walls and 180-ft.-span roof trusses to achieve the required space for a 200-meter indoor track. Precast panels also form underground tanks that retain storm water or water tapped from 650-ft.-deep geothermal wells.
“One hundred percent of the precast was fabricated less than 15 miles from the job site, which was both a financial and environmental plus,” Hudson says. “This and other factors contributed positively to our pursuit of LEED Gold status from the U.S. Green Building Council.”
Hudson notes that he and other administrators at NCC were very concerned about the insulation and thermal values that could be achieved. “Bio-based foam was used to insulate the precast concrete walls,” he says. “The precast combined with our mechanical system and other design features provides a comfortable environment for our students no matter what the outside temperature.”
ICF in North Carolina
In simplest terms, ICF involves hollow foam blocks that are stacked into the shape of a project’s exterior walls, reinforced with steel rebar, and then filled with concrete to provide an alternative to using a wood or steel frame. ICF was the choice for a new residence hall on the campus of North Carolina Central University (NCCU) in Durham. Construction on the Chidley North Residence Hall began in February 2010, and the 517-bed, 134,000-sq.-ft. project will be completed early this summer.
Derek West, project architect with Lord, Aeck & Sargent’s Chapel Hill, NC office says that ICF was a good building choice. “We looked at a variety of building structures and debated whether to use concrete masonry or ICF,” he says. “We determined that ICF was the best approach for this project.”
West says that ICF provides excellent insulation, which was an important consideration. “ICF is more expensive on the front end versus concrete masonry construction for exterior wall assemblies, but it also provides almost double the thermal insulation of concrete masonry with conventional insulation. When you look at the cost over the life of the building, taking into account energy savings, ICF will save money compared to a conventional concrete masonry structure.”
From a geographic and climate perspective, West notes that ICF is perhaps more beneficial where fluctuations between hot and cold temperatures are greater. Administrators who select ICF to build in areas of the country where temperatures vary more — such as North Carolina — may see more benefits from an energy savings perspective.
West echoes Farny’s comment about working with experienced suppliers and contractors. “In some areas of the country, builders familiar with ICF may not be as prevalent. It’s important to work with a company that understands the method’s limitations and its benefits in order to achieve success on a project.”