by Dale Mullikin
An old adage proclaims “If you want something done right, do it yourself.” This would be virtually impossible in today’s commercial construction where complex building systems, vast arrays of material choices, design configurations, and countless other variables require more expertise than anyone could ever muster alone. Still, some general contractors maintain this old-school work ethic.
“We’re an old-fashioned general contractor,” says John Calacci of Iowa City-based Calacci Construction. “We like to do our own work.”
His company generally places concrete and sets steel for all of their projects, then tackles framing, roofing, and insulation. It subcontracts work only when its internal expertise meets its limits. It helps the company owns much of the required heavy equipment.
As a union contractor, Calacci has access to hiring halls to support a peak employment of as many as 150 tradespeople. He also works closely with a variety of apprentice programs to hire and train multiple trades. Calacci acknowledges the difficulty of hiring all the talent needed to perform all of the work in-house, but sees a lot of positives for his clients in this approach.
“Self-performing as much as we do gives us comprehensive control over everything—quality quality, safety, schedule, cost, and profit,” says Calacci, whose company has been in growth mode since its 2008 founding. “Ultimately, tight control results in great efficiency, which is something we value quite a lot.”
Today, it does an annual volume of roughly $30 million, picking up projects throughout eastern Iowa in multiple sectors including industrial, healthcare, municipal, and commercial.
When it came time to construct his own new company offices, Calacci’s appreciation for long-term efficiency was the driving factor in most design and construction decisions. After a few years of leasing office space and telecommuting, constructing an office allowed him to get everyone under the same roof with room to grow. Completed in the spring of 2016, the new 1468-m2 (15,800-sf) office building is configured on two floors, with mechanical systems located in the basement. The main building is accompanied by a 111-m2 (11,900-sf) shop, along with ample site storage and space for equipment, materials, and staging. All these features were designed for functionality and accessibility in daily use.
Calacci looked into building strategies that would help the company reduce operating expenses during Iowa’s hot summers and cold winters. He opted to take advantage of the site’s ability to tap into geothermal heating through a ground source heat pump. Using horizontal wells drilled between 4.5 m and 9.1 m (15 and 30 ft) deep, the pump circulates fluid through plastic pipes in the wells, which is either heated or cooled by the earth depending on the season. The building maintains a steady temperature of 14 C (57 F) degrees, circulating cooler air in summer and warmer air in winter. Along with the heat pump, the new building also benefits from a high-performance thermal envelope, which helps maintain constant temperatures despite external conditions.
Since the architecture combines a glass curtain wall with punched window masonry, a tight seal required a bit of precision in materials and workmanship.
“To meet the International Building Code [IBC], walls have to have a complete thermal break,” he explains, “so we needed a masonry cavity insulation.”
Another challenge Calacci faced was the masonry face of the building, which lifts out and dips in and around, long vertical sections of glass—a well-executed undulation from solid to transparent and back. He explains some cavity sections were as much as 150 mm (6 in.) of void space, while other sections were just 50 mm (2 in.).
To effectively insulate this area, Calacci used pre-scored architectural-grade expanded polystyrene (EPS) insulation foam with a high compressive strength.
“[These] products come in a wide range of thickness,” Calacci says. “[This] really helped us fill in around some complex architectural detailing.”
Purchasing a pre-scored product allowed Calacci’s installers to easily create custom lengths by bending the insulation board along the perforations and snapping it into fitted pieces.
Calacci had previous experience working with EPS insulation, recalling his work on the new Children’s Hospital in Iowa City. His company used large geofoam blocks as a lightweight structural fill between an underground parking structure and a roadway plaza built above. This experience gave him an appreciation for EPS’ compressive strength and durability.
While many of the cost-effective sustainable strategies Calacci Construction employed on its project are commonplace, there was one application that was a first for the company. Adjacent to the new office sits Calacci’s 111-m2 (11,900-sf) shop, which includes 650 m2 (7000 sf) of heated space using an in-floor radiant heating system. Maximizing the thermal benefits required some innovating.
“We figured out how to embed 50 mm of [EPS foam] insulation within a cast in-place concrete wall,” says Calacci.
Creating a pan-wall that is 305-mm (12-in.) thick and 1.2 m (4 ft) up from the foundation, Calacci used two steel rebar grids and center-facing slab-boosters to sandwich a layer of EPS foam into the framework.
“[We] created a thermal break along the foundation walls that extends up 1.2 m (4 ft) above the floor,” Calacci explains. “But we don’t have any caulk joints to maintain the way you would with insulated precast panels.”
Dale Mullikin is a regional sales manager with ACH Foam Technologies, presenting more than 20 years of experience in expanded polystyrene (EPS) solutions for construction applications. He has conducted hundreds of educational seminars on EPS with architects and engineers all over the Midwest.