Architect Larry Deweese prides himself on a pragmatic, open-minded approach to problem solving. Case in point: a project from nearly three decades ago that still informs his design judgment.
“It was a large multi-purpose addition to a local church. I read about a building system that seemed just right for it, though I knew very little about it at the time,” recalls the principal architect of Oxford, Mississippi-based Howorth & Associates Architects. “The more I investigated, the more I liked what I saw. There seemed to be no downside, other than my own lack of familiarity with it.”
That was 1998. Today Deweese is arguably one of the region’s leading proponents of insulated concrete forms (ICF), a highly evolved building system known for installation speed, resilience, and energy efficiency. The system uses LEGO-like, EPS-foam-molded, steel-reinforced cavity blocks to form a cast-in-place, continuously insulated concrete wall with integral furring strips for applying both interior and exterior finishes.
“It’s a good tool for your toolbox,” Deweese says. That tool has served the Howorth team well for nearly three decades, helping them win commissions while differentiating their practice. Today Deweese is an ardent ICF advocate for at least seven reasons:
- Design Freedom. ICF manufacturers have adapted the system to meet many application requirements, including curved envelope applications. ICF is even used for pool construction.
- Project Speed. ICF construction is fast. The rapid stacking system is simple and less physically demanding than nearly any other building system. Deweese cites a major addition to a sorority house as an example. “The three-story addition went up quickly, basically a floor a week,” the architect reports. “It’s very installer friendly.” The single ground-to-roof system represents the work of up to six façade trades, including insulation and the air/vapor barrier. Fewer trades mean less coordination issues and errors. It’s almost a “one-and-done.”
- Resilience. A monolithic concrete mass is a formidable defense against wind, moisture, seismic activity, insects, and fire. Extreme resilience is a huge selling point for many owners, especially public officials and their consultants. “We designed an emergency management facility that required it to withstand a tornado hit and continue uninterrupted operation,” Deweese says. “ICF structures survive wind speeds up to 250 mph (F4 tornado). The fire station next door is also ICF.” And fire resistance? ICF is fire-rated for up to four hours, four times longer than stick-built construction without considerable upgrading.
- Labor. Deweese says ICF construction simplicity doesn’t require a highly skilled workforce, though he does recommend new users receive ICF manufacturer training. “While ICF construction isn’t complex, a few days of training really helps speed up workflow,” he suggests. There are also plenty of online instructional videos.
- Energy Efficiency. The thermal mass of the concrete typically means the HVAC system can be downsized. Compared to wood, ICF structures can require up to 44% less energy to heat and 32% less energy to cool.
- Sustainability. Concrete’s low cost and durability makes it a crucial building material. Innovative building systems like ICF help limit the environmental impact of concrete production and its carbon footprint, helping create a more resilient and ecologically responsible built environment.
- Acoustics. Solving for interior sound is a notable ICF attribute. ICF walls start at a 50 sound transmission class (STC) rating. Stick-built construction generally starts at a 38 STC rating.
Today Deweese is easing into semi-retirement, encouraged by the idea more and more of his peers now stock their toolbox with ICF as a proven building system solution for many project applications.
Learn more about how ICF construction simplicity, speed, resilience, and sustainability can support your next project.
